Frost

:For other uses of "Frost", see Frost (disambiguation).
Frost (c. 1999 - 2022), formerly known as Killer Frost and originally labeled Khione after the Greek goddess of snow, was Caitlin Snow's alternate personality, until she obtained a body of her own. She was also the girlfriend of Mark Blaine and the sister figure of Caitlin. Since she was a child, Killer Frost existed within Caitlin due to cryogenic experiments performed on the latter by her father, Thomas Snow, in an effort to prevent Caitlin from suffering from ALS. However, Killer Frost was suppressed until Caitlin's time with Team Flash, when her alternate personality began to reemerge. Originally, Caitlin's Killer Frost powers mostly amplified her insecurities and anger, changing her chemical balance, but the further she continued to use these powers, the further she changed. Eventually, after defeating Savitar, Caitlin developed a special partnership with her Killer Frost side, going on to analyze her condition, which resulted in Killer Frost becoming a full-blown split personality, the actions of whom Caitlin would largely not remember.
In a battle against Clifford DeVoe, Killer Frost disappeared as a result of DeVoe using Dominic Lanse's powers to create a mental block, which prevented Caitlin from accessing her alter-ego. After defeating Siren-X from Earth-X though, Caitlin discovered that cryogenic anomalies still existed in her DNA, without the presence of dark matter. After the team found out that Caitlin's father is actually alive, they discovered that he is also a cryogenic meta-human with an evil split personality, Icicle. During a battle with him, Caitlin is able to break through the mental block created, allowing Killer Frost to emerge. Cisco later gave Caitlin a mental activity dampener created by Harry Wells so she could communicate with Killer Frost. During a fight with Cicada, Team Flash discovered that Killer Frost was immune to his dagger (as she was not a dark matter-created meta) and could help defeat him.
Soon after defeating Mirror Monarch, both Frost and Caitlin suffered from immense recurring headaches, which seemingly led to them becoming separated from one another and Frost inhabiting a body of her own. Frost chose life in prison without parole and decide to pay for her mistakes that she made. The judge, the prosecutor and the jury were very lenient and offered no jail time and gave her an ultimatum to take the meta-human cure, but she declined and decided to take life in prison without parole and the judge gave her what she wants. After there was breakout at Iron Heights due to damage from the Force Storm, Frost briefly escaped to round up everyone else who fled before returning; as a result of her good deed, Frost was let out on bail. While resuming her duties on Team Flash, Frost began dating the reformed criminal Chillblaine. By 2022, Frost was traveling the world with Blaine for extreme sport dates.
Eventually, Frost became Hellfrost and confronted Deathstorm with her newly upgraded powers. After the two fought throughout the city, Frost absorbed Deathstorm into herself, killing her in the process.
==Biography==
===Original multiverse===
====Early life====
Around 1999, Caitlin Snow's father, Thomas Snow, discovered that his daughter inherited his ALS gene. Desperate to save her, Thomas began performing experiments of cryogenic gene therapies on Caitlin in an attempt to freeze the disease, just as he had done with himself. While the experiments were successful, Caitlin began exhibiting a dual personality, whom Thomas called "Khione" after the Greek goddess of snow. During one such incident, Caitlin fell off her bicycle during an accident and got hurt as a speeding car approached, causing her second personality to fully emerge. Caitlin would repress this memory and Killer Frost for years.
====Fighting Team Flash====
=====Kidnapping Julian Albert=====
17 years later, Caitlin's Killer Frost persona would emerge periodically and gradually increasing in frequency as her meta-human powers emerged, especially when dealing with her estranged mother. She was kept at bay for a while after Caitlin used power-dampening cuffs to stop her powers, and subsequently her other persona, from emerging. After using her powers to save Barry Allen from Savitar, Killer Frost's personality came to the fore, but Caitlin went to find Alchemy to try to get rid of Killer Frost. Caitlin used her ice powers to torture one of Alchemy's acolytes to try to find him, but left him frozen just before CCPD arrived. Caitlin then kidnapped Julian Albert to make him run a search algorithm to find Alchemy, hoping Alchemy would take away her ice powers, and eventually located another member of his cult. Julian managed to call the police, and the Flash arrived to try to talk Caitlin out of using her ice powers.
Caitlin stabbed him in the leg and escaped to find Craig, the cult member Julian found. Caitlin threatened his family, and he told her that he didn't know where Alchemy was or who he was, but that he had shown them the future where she was Killer Frost permanently. Cisco Ramon and Barry arrived to stop her from killing the acolyte, and they fought. Unable to escape, Caitlin gave Barry a kiss to try to kill Barry before being knocked out by one of Cisco's vibe-blasts. She woke up in the pipeline and tried to convince Team Flash she was back to normal, though they were unconvinced. After Wally West was cut out of the cocoon he was trapped in by Alchemy, Barry was forced to go to the pipeline to talk some sense into Caitlin. He let her out of her cell and asked her to kill him but, unable to hurt her friend, Caitlin managed to avoid killing Barry.
In early 2017, Caitlin was given a necklace by Julian that dampens her powers and also collects solar energy to charge it to ensure that it continues to work properly, thereby keeping Killer Frost at bay.
After Iris West was touched by Clive Yorkin, who had the power to disintegrate anything he touched, she was slowly dying. Caitlin was then forced into using her powers to slow down and stop the disintegration. However, in the middle of this, Killer Frost briefly took control and stopped saving Iris. She even taunted Julian, who ended up talking her out of it and allowed Caitlin to regain control.
=====Joining Savitar=====
After S.T.A.R. Labs was attacked by Abra Kadabra, Caitlin was critically injured by shrapnel and helped Julian perform her surgery. However, she later began dying from a seizure. Julian, Cisco, and H.R. attempted to resuscitate her, to no avail. In an effort to bring her back to life, Julian ripped off Caitlin's necklace and her powers caused her wound to heal, but once she opened her eyes, it was Killer Frost who emerged. She knocked everyone back with a huge wave of ice and emerged from the icy smoke with her hair fully white. She then attempted to kill them with beams of ice from her hands, even knocking Cisco and H.R. by smashing a window they were behind. Julian then attempted to grab her necklace and put it back on Caitlin's neck, only for Frost to destroy it with another ice shot. He told her that he cared for her, and she used this to her advantage, telling him to kiss her so she could freeze his head. However, before they could meet each other's lips, Cisco knocked her back over a table and into a wall with a vibe blast.
When the three men ran out of the room, Frost followed and found them attempting to hide in the pipeline. Just when she was about to kill them, Barry sped in and knocked her into a wall and told Caitlin that she could fight what was happening to her. She simply told him that she didn't want to and froze the doorway he was behind solid. When he searched the building for her, she was already gone. Later, while Killer Frost was walking through the woods, she came across Savitar. At first, she was startled until he told her not to be afraid of him as he wanted her to become an ally of his. She asked him why she should trust him and he revealed himself to be Barry Allen's time remnant. She then asked him what he needed her to do.
=====Hunting Tracy Brand=====
After joining Savitar, Killer Frost received a new suit and was sent to kill Tracy Brand at Central City University. When she arrived, Barry, Cisco and H.R. were already there trying to get her out. Frost entered by freezing and smashing a glass door and sending an icicle right for Tracy. However, before she could be impaled, Barry moved her out of the way with his super speed and told H.R. to get her out. He was then knocked to the ground by Frost's ice beam. As she was about to run after H.R. and Tracy, Cisco got in her way, she rubbed the fact that she was fully Killer Frost now in his face and shot him with an ice beam, knocking him over a counter and onto the floor. This was when Barry got up and used a flamethrower and his speed to launch fire at her, causing her to retreat. When she reported back to Savitar, he accused her of letting Barry and Cisco go on purpose and told her all she had to do to be a god like him is kill Tracy. 
She later showed up outside Jitters and was about to attack Tracy and H.R. again until Barry, Julian and Cisco showed up, allowing H.R. and Tracy to flee the scene. Frost chased after them by creating a path of ice that flew through the air with Barry chasing after her, attempting to get her to return to Jitters so Cisco could shoot her down. However, when she reached Jitters, Cisco couldn't shoot her down as he still saw her as his friend, and this gave her the opportunity to shoot a beam of ice at him, so Barry was forced to run in front of him and take the shot, sending him down a flight of stairs. Killer Frost then reached the ground again and walked over to Barry, taunting him. She then stabbed him in the leg again, stating "scar tissue is much more sensitive than regular tissue". 
After Cecile Horton left the West house, Frost grabbed her and threatened to kill her if her boyfriend, Joe West, didn't arrive at a certain address that Cecile was being held in. Joe attempts to pull his gun on her but is hit with an ice blast and thrown over an end table. Later, Team Flash arrived in a warehouse that Cecile was being kept in and Frost appeared out of the shadows and taunted Tracy about killing her and asking them to hand Tracy over in return for Cecile. Barry then attempted to talk to get Caitlin to snap out of it and let Cecile go but to no avail, she then reveals that she knows Cisco is hiding up in the rafters and sets off a bomb forcing him to quickly open a breach and land across the warehouse, knocked out and in a pile of boxes.
Frost then went to shoot Joe with an ice beam only for Barry to run in the way and get frozen on the ground. Before Frost can do anything else, Cisco shot her in the back with a vibe blast. However, she quickly gets back up and the two shoot their respective powers at each other. At first, it seemed Frost was winning until Cisco mustered enough power to knock her back into a wall, knocking her out. Savitar then appeared and sped her out of the warehouse.
=====Regaining Savitar's memory=====
Since Savitar was a time remnant of Barry, he remembered everything that Barry did, so Team Flash wiped Barry's mind to prevent Savitar from knowing their plan. After they did this, Killer Frost wanted their plan to speed up and approached Savitar's kneeling armor in order to get to work only for him to abruptly stand and hold Frost against a wall by her throat. She asks what he's doing but he only asks the questions "who are you?" and "who am I?". She then realizes what's wrong and travels to S.T.A.R. Labs to get help from Team Flash. When Cisco, Wally and Julian return to the Cortex, Frost was waiting for them. Wally attempted to speed towards her but realized that he had lost his speed and she tells them that she knows why. The three were discussing with each other to see if they should trust her or not until Barry, Iris and Joe walked in, wondering why they looked so worried when Killer Frost walked out from Caitlin's old lab, causing Joe to pull his gun on her. Everyone told him to stand down and he did so. Barry, still in his amnesia like state, asked if Frost was some kind of supervillain, causing her to look at him with an "obviously" look on her face. He then left the room, which left Frost with former allies of Caitlin. She explains that what Barry remembers, Savitar remembers, and the team could just teach Barry everything and beat Savitar. However, there were lots of villains in Central City and no Flash to stop them at all.
She then convinced them all that they needed to work with her to bring back Barry's memories. Cisco and Julian worked with Frost and while they worked, Cisco attempted to remind her of all of the memories they had working on the particle accelerator. It seemed to get through to Caitlin but Frost quickly took over again. Later, the three ran back to the cortex and turned on the TV, only to see that a building had been set ablaze by an infamous arsonist. Frost ends up helping Barry recover his memories and put out the flames. After everything had calmed down, she attempted to leave only to be stopped by Barry, Cisco and Julian. They tried to tell her that she was their friend and could be again with Julian also saying that he loves her, but she replied that she never loved any of them and entered the elevator. Once the elevator started its descent, Caitlin briefly took over only for Frost to bury her again.
=====Final fight=====
Killer Frost approached Savitar to ask what he was working on in his suit and he replied that his suit was damaged during his fight with Barry. Frost then asked if they were a team, referring to them both as "Barry and Caitlin". He looked up and replied that he wasn't Barry and she wasn't Caitlin. She then asked if Savitar was really going to kill Iris after all of the memories he shared with her. He asked if she is having second thoughts about their plan and she only shook her head, visibly scared. Memories begin to flood into Savitar's head and she asked what he saw. He explains that Barry went back in time to ask for Leonard Snart's help to retrieve the power source for their weapon to use against Savitar. Frost asked if she should stop them but Savitar just said that it doesn't matter. Later, Cisco got a vibe of Killer Frost in a forest, waiting for him to come fight her. Cisco then arrived at her location and the two began to fight only for Frost to overpower Cisco, flooring him and giving her a chance to kill him.
However, before she could finish Cisco off, Savitar sped in and commanded her to spare his life. Confused, she asked why he needed to live. He explained that Iris had survived because H.R. had taken her place and died, and that they needed Cisco to build something for them. H.R. died because Killer Frost took H.R. back to Savitar to be murdered when H.R. was disguised as Iris West in an escape attempt. The three then speed back to Savitar's lair. Savitar explained to Cisco that he needed to convert the Speed Force bazooka into a quantum splicer in order for him to survive without the time paradox catching up on him. In order to make Cisco begin working, Savitar also threatened Frost's life, knowing that he would never get over the death of his best friend. After Savitar had left, Frost asked Cisco if he had finished the splicer and he nodded. He then attempted to tell her that if she continued to work with Savitar he would eventually kill her after he didn't need her abilities anymore, but she disagreed and thought they would always work together.
Right afterwards, Savitar returned to his lair. He asks if everything is done and Cisco explained that it is. Frost then began to raise her hands and Cisco repeated that Savitar would kill her but she doesn't listen and fires an icicle straight at his chest only for it to be stopped by a breach. The two villains looked shocked until Cisco's girlfriend, Gypsy, leaps into the lair through another breach and pulls Cisco into another one. Killer Frost asks Savitar if he cared that they escaped and he replied that it didn't matter since the splicer was ready. The two arrived at the outskirts of a forest and began to use the splicer to make sure Savitar would live, but they are stopped by Jay Garrick, who escaped from the Speed Force.
They then turned to see that all of Team Flash had arrived. Frost told Savitar to go whilst she fought Cisco and Gypsy. She was quickly thrown to the ground which gave Cisco the chance to kill her but he refused and gave her a cure that was made by Caitlin's mother and Julian. She seemed very hesitant but once Savitar grabbed Cisco and was about to kill him, Caitlin Snow managed to take over Killer Frost and buried her instead and she saved Cisco's life. Killer Frost and Caitlin never apologized to Cisco for her attempts to murder him. After Frost's defeat, Savitar was also erased from existence and Caitlin left soon after.
====Redemption====
=====Working for Amunet Black=====
After this, Caitlin joined Amunet Black's criminal organization and worked in her club. Killer Frost also resurfaced to do jobs for Amunet and ended up becoming one of her favourite henchmen. One of those jobs was torturing and maiming Amunet's enemies so that they lost fingers and toes.
When Caitlin was working her shift in Amunet's nightclub, she was approached by Cisco who asked her to rejoin the team. She ended up accepting his offer and helped them get Barry out of the speed force. When she returned to the club to quit the criminal organization she confronted Norvock and told him about her decision. When he grabbed her by the arm, it caused Killer Frost to reemerge and she managed to bash his head on a nearby machine. She then threatened him and walked out of the club. She was about to go on a spree through Central City until Caitlin regained control and Frost was buried once again.
When an alarm signalling an unauthorized breach went off in S.T.A.R. Labs, Killer Frost briefly attempted to take over Caitlin but was buried and wasn't able to take control.
=====Joining Team Flash=====
After Caitlin received a note from Amunet signalling her return, she attempted to get a plane out of the city but was invited by Iris and Felicity Smoak to go to Iris' bachelorette party. When they were sitting at a table in a restaurant, Norvock approached them and told Caitlin to go with him but she refused. He then displayed his meta-human ability, an eye-snake. He attacks everyone at the table and when Cecile, Felicity and Iris are all down, Killer Frost emerged and transformed in front of everyone's eyes. She then shot a beam of ice at Norvock which knocked him through a window. The women then return to S.T.A.R. Labs and they asked how Frost was still alive since they believed that Caitlin had gotten rid of her. Frost then explains that she is like a split personality and while Caitlin sleeps she is the one in control. She also retrieves her new suit from a large black bag and leaves to go and find Amunet Black. When she reached Amunet's club, Frost threatens her bodyguards to get past them and is greeted by Amunet herself. The two women and Norvock then enter a back room where Amunet kept a meta-human hostage and used his psycho-active tears as a drug. She then asked Killer Frost if she wanted to rejoin her and they could run Central City together as gods. Frost, however, refused Amunet's offer and the two prepared themselves to fight each other until Iris ran in between them and managed to get Killer Frost out of there and back to S.T.A.R. Labs.
The girls asked Frost how she knew Amunet and she explains that she and Caitlin both worked for her and actually ranked very high in her criminal organization. She also admitted that she'd tortured Amunet's enemies by freezing their fingers and toes off. Frost then told them that she planned to retreat to another Earth to escape Amunet and live her own life how she wanted, without Caitlin. Iris then attempted to talk Killer Frost out of leaving and told her that she and Caitlin could live together as one. However, Frost only threatened to freeze her hand off and leaves the room to go fight Amunet. The two women meet under a bridge. Frost didn't expect to see Amunet herself and was caught off guard when she launched a large piece of metal into Frost's shoulder. She then attempted to recover by launching ice blasts at Amunet but she only deflected them with a metal shield and launched two more large pieces of metal that floored Killer Frost.
Amunet then picked her up by the collar of her jacket and started to throw punches that made Frost retreat back into Caitlin's mind and allowed Caitlin to retake control of her body. Caitlin then returns to S.T.A.R. Labs and decided to stay while Iris, Felicity and Cecile fought Amunet. However, when things went south and Felicity and Iris were captured, Caitlin appeared in front of Amunet and her henchmen and allowed Killer Frost to take control. As Iris and Felicity ran behind Frost, Amunet ordered her goons to kill them but before any of the bullets could hit them, Frost made a giant igloo-like ice dome-shield to protect them. Iris then told Cecile to turn on a giant magnet so Amunet couldn't use her powers. She did as Frost had instructed, and rendered Amunet powerless. Frost then formed an icicle, ready to stab and kill Amunet until Iris managed to talk her out of it and they all return to the lab. Despite all Iris did to help her, Killler Frost never apologized to Iris for Killer Frost working with Savitar to murder Iris. Killer Frost never apologized to Cecile for threatening to murder her. Later, the boys from Barry's bachelor party arrived back in the lab to find Killer Frost waiting for them in the cortex. They are shocked to see her at first but she slowly transformed back into Caitlin and explained to them what was going on with her. After this, Caitlin and Killer Frost began working together and Frost became a fully fledged member of Team Flash.
=====Crisis on Earth-X=====
During Barry and Iris' wedding, the priest was killed by Nazis from Earth-X. Cisco then told Caitlin to let Frost out and when she did, Mick Rory noticed her and took quite a liking to her. Frost created a giant icicle around her hand and killed a few Nazis on the aisle of the church. She then reappeared to fight the Dark Arrow but was ultimately overpowered by him and thrown against the wall of the speed lab. Caitlin, Cisco, Harry and Dinah Drake were locked in the pipeline by the Nazis but were all freed when Iris and Felicity found them and opened their cells. A robot from Earth-X attacks S.T.A.R. Labs, and everyone present from Team Arrow, Team Flash, and Team Legends teamed up and destroyed him. Later, in the final battle, Frost uses her ice path ability to fly herself, Amaya Jiwe and Zari Tomaz up to the Earth-X version of the Waverider, the Wellenreiter, and destroy it. After the Nazis are defeated, Barry, Iris, Felicity, and Oliver Queen all get married and the heroes return to their respective Earths and times.
=====Battling The Thinker=====
After Barry was wrongfully accused of murdering Clifford DeVoe, he was in his trial when the city was threatened by a meta-human Cisco nicknamed Fallout. Killer Frost was needed to cool him down or else the entire city would be nuked by him. Cisco and Harry Wells had to traumatize Caitlin in order to get Killer Frost to emerge and when she did, she and Cisco were breached to Fallout's location. At first, Frost seemed to have won by simply freezing Fallout, but he broke out of the ice and shot Frost with a beam of energy, sending her flying back into a bus stop and also knocking her unconscious. Fallout was then defeated by Barry and Cisco.
Frost helped Vibe when they were sneaking into Trickster and Prank's hideout. When they both saw what appeared to be hostages, they ran towards and began to set them free until they heard a noise behind them and saw a group of Beebo toys that Frost froze and shattered with her powers. When they turned back to the hostages they revealed themselves as Trickster and Prank in disguise and put power-dampening cuffs on Frost and Vibe, causing Killer Frost to disappear and Caitlin to reemerge. Both Caitlin and Cisco were then saved by the newest member of Team Flash, Ralph Dibny.
When Ralph began to doubt himself, Caitlin went to his office to try and give him a pep talk but when he wouldn't listen she let Killer Frost out and she talked to him. He told her the problem was that he believed all of his friends would leave him as his friends in the past have. Frost then told him that the people in Team Flash never gave up on her and that they would never give up on him, which lifted his spirits. Frost lied by not telling Ralph about all the attempts she made to murder members of team Flash, including the fact that she was an accessory to H.R. Wells' murder when she took him to Savitar knowing he'd be murdered. He even called her "Frosty Oprah". When Barry Allen attempted to escape from prison because of Amunet who was looking for meta-humans to buy and recruit into her organization, Vibe and Killer Frost breached into Iron Heights and asked him to come back to S.T.A.R. Labs with them, but he refused, not wanting to become a fugitive. Clifford DeVoe was also alive and took over the body of former Team Flash enemy, Becky Sharpe.
When the team heard about an attack on the CCPD at an airfield, Killer Frost, Vibe, The Flash, and Jesse Quick traveled there to help them. Once they arrived they were able to quickly take out the henchmen and were ready to take out their boss, Veronica Dale, until she revealed that she was about to activate a nuke. However, before it destroyed all of Central City, Barry and Jesse entered Flashtime and attempted to figure out a way to deactivate the nuke. Jay Garrick also came from Earth-3 to try and help them. Eventually, the three speedsters thought it was a good idea to cool down the nuke and went to take Killer Frost into Flashtime. Once in motion with the speedsters, they brought her into the container where the nuke was located and attempted to send a beam of ice to cool it down, however, Frost began to burn up and her powers had no effect on the bomb. In order to stop Frost from burning up, Barry puts her back into normal time. She pleaded Barry to not let Caitlin die. Barry ends up taking Iris' advice and stops the nuke from destroying the city with help from the Speed Force.
====Disappearance====
Team Flash came up with a plan to attack DeVoe head on and enter his pocket dimension. Killer Frost, The Flash and Vibe then prepare to enter the pocket dimension and defeat him. However, when they arrive, they realize that he wanted them there so that he could attack S.T.A.R. Labs with no issues. Harry, Joe and Iris were all attacked by DeVoe and his wife, Marlize. Iris was able to bring the three back and they attempted to fight DeVoe but he ended up killing Ralph and stealing his body. He then knocked Barry and Cisco back and when Frost attempted to stab him, he stole her powers and appeared to kill Killer Frost as well. He then knocked Caitlin back into a wall, unconscious. Caitlin underwent tests from Cisco and Harry, who were both unable to find any trace of dark matter in her body.
After Team Flash defeated Siren-X, the Earth-X doppelgänger of Laurel Lance, Caitlin found out that Killer Frost is still alive but without any dark matter in Caitlin's body, she is unable to appear.
The team began to help Caitlin to try and get Killer Frost to reemerge, they ran tests that involved Cisco shooting her with his vibe blasts, which caused nothing to happen. However, while Barry and Cisco are fighting DeVoe, Caitlin appeared and used Leonard Snart's gun on DeVoe in an attempt to get Killer Frost to return, but to no avail, and becuse of Caitlin's interference DeVoe almost killed Gypsy. Caitlin never apologized to Gypsy or Cisco for nearly getting Gypsy killed by DeVoe.
Still desperate to get Killer Frost back, Caitlin finally went to Amunet for help. She led the team to believe that they needed Amunet to help defeat DeVoe and they all managed to get her to help them. Caitlin then struck a deal with her and told her that if she could get Killer Frost back she would do one favor for her. However, it's revealed that Amunet didn't know how to bring her back but still gave Team Flash an item that could help defeat DeVoe.
When Caitlin went to therapy with Dr. Finkel, she revealed that Caitlin had been repressing a memory from her childhood, a memory which was very traumatic for her. She later asked Cisco to vibe her to this memory and see what happened only to see her younger self get hit by a car and then transform into Killer Frost. This revealed that Frost had been inside Caitlin even in her early childhood, before the particle accelerator explosion.
In the final battle against DeVoe, when Cecile went into labor, her powers which she received from her pregnancy kicked in and Killer Frost briefly inhabited her body. She grabbed Caitlin's arm and told her that she had found Thomas and he had been that way all the time.
====Return====
=====Defeating Icicle=====
Team Flash had discovered that Caitlin's father's death certificate was a fake and that he was actually alive. Barry, Caitlin and Cisco eventually tracked him down to a warehouse owned by Tannhauser Industries.
However, it was later discovered that he was also a cryogenic meta-human that had an evil split personality that attacked the team. The personality wanted to use a serum, that Caitlin reluctantly created, to kill off Thomas for good and inhabit the body himself. Just as he was about to inject himself, Caitlin managed to break through the mental block that DeVoe had created, allowing Killer Frost to emerge and shoot him back with an ice blast. He quickly attempted to convince Frost to take the serum as well and work with him but she refused, stating that Team Flash was her true family. As she walked towards him, she stood on and destroyed the serum. She created an ice-fist and began to punch him but stopped as Thomas' personality emerged and spoke to Caitlin. This turned out to be a short reunion as the evil personality reemerged and shot her with an ice blast, proceeding to use two ice blasts to launch himself into the air and escape. Later, Caitlin discovered that she could use the cerebral inhibitor to speak to Frost through the mental block and the two began to catch each other up.
=====Meeting Cicada=====
During Thanksgiving, Caitlin, Cisco and Sherloque Wells decided not to attend the party at Barry and Iris' apartment, causing Killer Frost to emerge. She questioned they're decision of eating by themselves instead with friends who care about them and proceeded to walk off to the party, asking if they were coming or not.
During a battle with Cicada, the entire team was taken down by him and just as he was prepared to stab Barry with his dagger, Killer Frost emerged and fired an ice beam at him, sending him flying into a nearby van. He quickly stood and escaped the scene. The team later realised that Frost is immune to Cicada's dagger and could be useful in defeating him.
=====Elseworlds=====
Killer Frost and Elongated Man were sent to Ivo Laboratories to help deal with A.M.A.Z.O., who had been accidentally activated by an inexperienced Oliver Queen using Barry's speedster abilities. The two and Officer Jones were unfortunately not strong enough and as they were floored by the android, it absorbed the two meta-humans' abilities, using Frost's abilities to fly through the roof and escape.
After traveling to Gotham City, Kara Danvers used Caitlin to gain access to Arkham Asylum, convincing the nurse that she was a mentally ill meta-human, even quickly flashing Frost's eyes. After they got inside, a riot began and the two split up. Eventually, Caitlin came across a frantic Nora Fries who was searching for something amongst the shelves. When Caitlin attempted to help her, Nora blasted a beam of cryogenic smoke at her, causing Killer Frost to emerge and engage in a fight. When Nora grabbed her husband's cryo-weapon, Frost asked for some assistance over her comms but before Barry or Oliver could arrive, Nora blasted her back through a table, knocking her unconscious.
=====Sabotaging the cure=====
Whilst Caitlin was stitching up Cisco's hand wounds, Killer Frost briefly emerged in order to freeze the wounds. Later, after Cisco began working on the meta-human cure, Frost appeared behind him and destroyed his work with a freeze blast. When asked what she was doing, Frost simply stated that a meta-human cure was not needed and that her and Caitlin were doing fine together. However, Cisco explained that he wanted to cure all those who did not ask for their powers, including himself, who wanted to grow old with someone and have a normal family. When Weather Witch and Silver Ghost were partaking in a dangerous joyride in Central City, Nora recruited Killer Frost for help. Frost created a giant ice wall in the road that, unfortunately, didn't stop the two as the car they were driving was able to phase through the wall. After the two ultimately escaped, Nora asked Frost if she was the one behind the car's control loss, to which she was confused.
After Caitlin supported Cisco's decision and began working on the cure as well, Frost then emerged and destroyed her work as well, much to the shock of Ralph, just as Barry walked in needing help on a mission to protect meta-humans from Cicada. Frost suggested they start looking in Amunet's abandoned club where they discovered a distraught Norvok using the club to hide out in. The group informed him on the situation and asked if he wished to help them save the other meta-humans, which he agreed to. After one meta began to go against the plan, Norvok informed her of a fellow meta-human's death at the hands of Cicada, being so distraught, he left the room with Frost following closely behind. When they were alone, Norvok explained his past of working at the Central City Zoo, where he obtained his abilities and the reason he only looked out for himself. After he left, Ralph sat to speak to Frost and asked if she was just as afraid as Norvok, about losing Caitlin. Before she could respond, Barry returned with another meta-human but left again to track down Peek-a-Boo.
Later, Frost and Ralph finished their heart-to-heart as she explained how afraid she was that Caitlin would one day grow tired of her and take the cure herself. Killer Frost didn't remember that she was not a dark matter meta, and the cure wouldn't work on her. Norvok then entered and announced that it was time for the meta-humans to leave, however, before the chopper could take off, Cicada appeared as Ralph attempted to get the metas to safety. Barry and Frost both stayed in order to fend Cicada off but Barry was ultimately unsuccessful, being launched into a large pile of crates, unconscious. Frost then fought Cicada head on, even being able to draw blood by cutting him with an icicle, however, he managed to generate a large blast, knocking her backwards, causing her to be disoriented. Just as his dagger was about to hit Frost in the back of the head, Caitlin psychically warned her, allowing her to swiftly dodge the weapon with ease and also freeze it long enough for Barry to gain back his powers. However, Cicada managed to escape into hiding with Team Flash believing he would stay hidden for a while longer. After Caitlin resurfaced, Frost gifted her with an apology and also a crucial piece needed to complete the meta-human cure, Cicada's blood.
After Iris experienced a run-in with Cicada on his property, Barry, Ralph and Frost all rushed to her aid. Once they arrived, he was gone but Iris exclaimed that she knew how to inject him with cure as she had discovered his weakness.
Cicada later managed to kidnap Iris and hold her hostage on a rooftop, worried for her mother's life, Nora rushed Frost to the location and Frost immediately created two icicles ready to fight. However, she did not notice Cicada's dagger behind her and it ultimately stabbed her in the back, killing her. Desperate to help, Nora ran back in time and ran back to before Iris was kidnapped, when Frost and Caitlin were both alive. After resetting the timeline 52 times, failing to save each Team Flash member, Nora finally let them help her come up with a plan to make sure no one died. As Iris and Nora distracted him, Frost, Ralph and Cisco all appeared on the roof and shot at Cicada but before the dagger could hit one of them, Nora briefly reversed time and made it stab Cicada instead, forcing him to retreat.
During Grodd's return, Caitlin and Cisco's minds were both controlled by him. After Cisco was locked in the pipeline by Barry, he witnessed Caitlin giving Grodd a device he used to enhance his psychic abilities, however, before he could pursue the Gorilla, Frost emerged and shot Barry with an ice blast, allowing Grodd to escape.
=====Meeting the New Cicada=====
When the Team learned of Cicada's plan to murder his next target, Philip Master, Frost managed to quickly be breached in and switch places with Master, catching Cicada by surprise and giving Barry time talk him down. When Frost returned to S.T.A.R. Labs, Nora asked how long the dagger would be out of action and she explained that Barry would only have around 60 seconds. When Barry eventually failed and was beaten, Frost quickly breached back to the alley and attempted to knock Cicada out only for him to escape once again. Later, the team managed to get him to the lab and talked him into taking the cure. However, during his surgery by Dr. Vanessa Ambres, S.T.A.R. Labs' power suddenly shut down and a seemingly new Cicada broke in and attacked the team. They all attempted to battle her but were all immediately defeated as she took the original Cicada back to her lair, murdering Dr. Ambres in the process.
=====Icicle's return=====
After Icicle attacked Tannhauser Industries, he also kidnapped Caitlin and her mother, placing power-dampening cuffs onto Caitlin's wrists to prevent Frost from emerging. However, when he hit Caitlin with an ice blast, it also froze her cuffs, shattering them and setting Killer Frost free. When she confronted him, he had already placed her mother in a freezing chamber and then quickly fled. When Barry arrived, Frost instructed him to save her mother and she set off after Icicle, the two of them creating separate ice paths to take flight on. Eventually, Frost managed to shoot him off his path but he also managed to ambush and stab her in the shoulder, forcing Killer Frost back and bringing Caitlin out. However, before he could kill her, Thomas overtook Icicle and was reunited with his daughter. Tragically, the reunion was short lived as Cicada quickly showed up, focused on killing Frost only for Thomas to sacrifice himself to save his daughter. He then died in Caitlin's arms as his wife watched on.
Still grieving from Thomas' death, Killer Frost remained in Caitlin's mind and barely ever emerged. While Caitlin and Ralph were visiting the Tannhauser research lab, he eventually talked her into coming out and freezing up a hole in the roof, cursing him in the process.
=====Defeating Cicada and Reverse Flash=====
After the team had discovered Cicada's plan of releasing a virus into the city to wipe out meta-humans, Killer Frost, Barry, Ralph and Cisco managed to ambush her at CCPD and render her unconscious. While Cisco deactivated the device, Frost, Ralph and Barry did their best to distract her but the three of them were ultimately defeated. However, Cisco eventually deactivated the device and knocked Cicada to the ground just as Frost threw the mirror gun Barry's way. As Barry shot the gun, Ralph screamed for him to stop. Ralph ended up jumping in the way of the gun, causing his body to uncontrollably misshape, giving Cicada time to escape. The team later tracked down her lair and devised a plan to administer the cure to young Grace so that Cicada would cease to exist. Once they reached the lair, the team breached Cicada back to S.T.A.R. Labs in order for Nora to speak with young Grace and by the time she does, Cicada had already returned and was about to kill Nora just as Barry shot the dagger. She then began to be erased from existence and the team briefly believed they had ended it but didn't realise that their actions had just set Eobard Thawne free.
After Barry and Nora were defeated by Thawne, the rest of the team breached by their side and he greeted them individually, including Frost. They all then managed to use their individual abilities to overpower Thawne and ultimately defeated him. However, he ended up escaping after Barry realised that their actions had caused Nora to be erased from existence as well. Later, Cisco ended up taking the meta-human cure but didn't leave S.T.A.R. Labs without gifting Frost with something, a new suit.
====Preparing for Crisis====
=====Starting her own life=====
After the death of Thomas, Caitlin began to notice Frost acting odd and, even at some points, refusing to emerge. Later, after Caitlin and Frost's near-death experience of almost being sucked into a black hole at Jitters, Frost wanted to start living her own life in order to experience new things, however, she did not know how to ask Caitlin. When Ralph managed to trick Frost into coming out, he confronted her about her feelings and she confessed that she wanted to live her own life but was afraid to ask Caitlin if she could take over. Ralph explained that she should ask Caitlin how she felt about the subject and left her with her thoughts.
After another black hole opened in the middle of Central City, Frost and Ralph both traveled to the scene, Frost finally donning her new suit. She managed to shoot at a newspaper stand that almost hit Joe and witnessed Barry willingly run into the black hole in order to stop it from the inside. However, it seemed as though he would not return and the entire team looked worried and shocked until he came running out of it again as it closed for good. Back at S.T.A.R. Labs, Caitlin and Frost spoke to each other about her taking control for a while and attempting to live her own life. Caitlin was happy to give Frost this chance and her body was quickly taken over as Ralph entered the room. She asked him where she should start just as he placed down the second version of the "Book of Ralph".
During her first day out as regular person, Frost was brought to an art showing by Ralph and Cisco in order to experience an actual public event. Before entering, Cisco injected Frost with a nanite developed by Ray Palmer that allowed to her to sound like a regular human and blend in with society. Once inside the exhibit, Frost and Ralph toured some artwork, with Frost declaring that the pieces weren't art at all, but in fact garbage, even going as far as to insult Kamilla's work. Later that day, whilst Frost was supposed to be monitoring the vitals of Chester P. Runk, she focused instead on attempting to draw a photo of Khione to no avail. She was then comforted by Cisco who she then confessed her feelings of guilt to who advised her to make her mistakes right. However, Killer Frost never apologized to Cisco (or Kamilla ) for trashing his girlfriend's photography.
After Barry's fight with Ultraviolet, he returned to S.T.A.R. Labs severely sub burnt from her UV Rays and discussed her training within a secret organization with Frost, Ralph and Cisco. He then asked about a collection of art that had taken up space in the med bay, with Frost explaining that she had purchased all of them with Caitlin's credit cards in order to support the artist's "inner life".
=====Learning of the crisis=====
After being informed of the impending death of The Flash by The Monitor, Barry and Iris sat down with the rest of the team and told them of their fates in the near future, being wiped out by Antimatter. Seeing the Frost was visibly angry, Barry decided to help train her for a future without him first by bringing her along to the scene of a crime. As Joe and Barry investigated, Frost attempted to speed the investigation up until she and Barry realized that the perpetrator killed for dark matter, allowing Frost to realize that Ramsey Rosso could be behind it. The two then arrived at Rosso's lab and Frost was quick to threaten him with an icicle held at his throat, only to be talked down by Barry. This allowed Ramsey to clearly see her face and he realized that Frost and Caitlin were in fact the same. As Ramsey discussed his work with the two, Barry believed that he could help in the investigation into the criminal killing for dark matter; however, Frost was quick to distrust Rosso and was reluctant to go along with Barry's plan.
While Barry spoke with CCPD over the phone, Frost waited with Rosso who requested to talk to Caitlin about going behind her back to experiment with dark matter from Kord Industries. However, Caitlin refused to keep listening and Frost quickly shut down the conversation just as Barry returned to offer information on a suspect, Mitch Romero, who was known by Frost to be a top gun runner in the city. Barry then received an alert about a robbery at Mercury Labs by Romero, who had become a zombie-like creature. When The Flash and Frost arrived, she used her powers to launch Romero out a nearby window into the street below, receiving a lecture from Barry on their no-killing agreement. In order to work out her frustration, Frost trained with powers on a S.T.A.R. Labs test dummy before Barry entered the room to try and talk with her. In order to get her to talk about what was bothering her, he challenged her to try and hit him with her powers only for her to finally give up and proclaim that she was angry her new life would be erased by the crisis. Now feeling better, Frost agreed to help Barry finally stop Mitch Romero for good.
After Romero broke into S.T.A.R. Labs, Barry managed to lure him into the pipeline with a vial of dark matter and locked him up. However, he then managed to break out, forcing Frost to use her powers to freeze him in place. After he injected himself with extra dark matter, she then realized that it is his fuel source and too much of it could stop him. Barry quickly retrieved all of the dark matter that was kept in the lab and injected Romero with them, finally exploding and killing him for good. Later, in order to allow Frost to live her life with what time she had left, Barry offered to throw her a thirtieth birthday party in S.T.A.R. Labs,
====Anti-Monitor Crisis====
Frost goes to Waverider with the other heroes. When Ralph arrives and introduces himself, Frost tells everyone to ignore him, as he is new, and this is his first crossover. Frost and Cisco are both in the control room and Cisco is excited when he announces he is trying to determine where the antimatter Wave-Particle is on Earth, to locate the source of the waves and he has discovered its located at a subterranean region very close to them. Excited, he tells Frost to meet him in the cargo bay.
Frost and Cisco make it to the end of the hallway and they are standing before a wall encrypted with a set of symbols. A total of seven hieroglyphics. Both of them are interrupted by the presence of Pariah he re-introduces himself to the group, insisting he is no longer Nash and has only arrived to bear witness to tragedy. When pressed as to what happened to him, Pariah tells his tragic story and they ask Pariah if he remembers how to open the door, but he does not.
They open the door and enter the Nexus. Barry joins them and they see the canon antimatter and a blurry running.
Frost questions if the blur is alive. Barry uses his speed to run forward, only to be very shocked and surprised to see Barry Allen from Earth-90 continuously running at light speed on a treadmill. The anti-Monitor corralled his speed and used it to build his antimatter cannon, which he tested by destroying the first earth, Earth-2. It is only then, that they realize both Harry and Jesse are now gone. It is during this time they realize Pariah is missing.
Pariah reappears and brings Black Lightning with him. They have a brief conflict but Black Lightning decides to help them. Eventually, the Earth-90 Flash then decides to sacrifice itself and they flee back to Waverider, where Harbinger appears and reveals herself to be possessed by the Anti-Monitor. The heroes try to stop him but he uses his powers to disable them. Then, Pariah transports the paragons to Vanishing Point and the Anti-Monitor destroys Waverider with an anti-material wave, killing the remaining heroes together. But she was restored a month later, after the Paragons and the Spectre created a new universe.
====Erased future====
According to Craig, a member of Savitar's cult, Caitlin would have been described as being "glorious and powerful", and Savitar had "special plans" for her, which did come true as she helped him and he needed her to kill Black Flash.
When Barry visited a possible future, in the year 2024, it is revealed that Caitlin allied herself with Savitar. Moreover, during a climactic battle, Vibe's arms were frozen and shattered by Caitlin, forcing him to replace them with bionic arms and subsequently making him unable to use his powers. Caitlin, still as Killer Frost, has been locked up in Iron Heights, and still refuses to divulge the identity of Savitar, with Julian as her caretaker.
====Altered reality====
After John Deegan used the Book of Destiny to rewrite reality and made himself "Superman", Caitlin and Killer Frost's lives were rewritten. It appeared that Frost had fully taken over and worked under Deegan as one of his prime soldiers. After he returned to his base, Frost and John Diggle applauded his actions but he quickly made them stay quiet and exclaimed that the Trigger Twins had escaped him. Diggle and Frost quickly assured him that they would be captured just as a warning from the pipeline alerted the room. Frost explained that it must have been "Subject 1" but "Superman" quickly explained that he would take care of her himself.
Later, Frost traveled down to the pipeline to speak with Agent Danvers and asked her to go home but became skeptical when she refused. She asked if she had boyfriend trouble but Alex just explained that she thought the work they do is important and she wouldn't change. Frost simply shrugged and left the pipeline. After Kara had managed to get through to Alex, the two attempted to escape Deegan's base but were confront by him, Frost and Diggle. However, a breach opened and Barry, Oliver and the real Superman came through and the two supermen broke through the ceiling and began their fight whilst Diggle and Frost fought Oliver in the elevator. The two were ultimately beaten by him and thrown in the pipeline. This reality was later returned to normal after Superman used the Book of Destiny to repair it.
===New multiverse===
At some point in Earth-Prime history, Frost was known as "Killer Frost". Upon seeing her, most know her by that name, so she must correct them.
Frost's Earth-1 memories were restored by J'onn Jonzz, when he came to S.T.A.R. Labs while Caitlin was treating Nash Wells. When Nash discovered that the Anti-Monitor was still alive, he, Ray Palmer and Ryan Choi began to develop a shrink bomb to trap the Anti-Monitor into an eternity of shrinking, since he couldn't be destroyed. Frost teamed up with Mick Rory, whom Sara had sent to S.T.A.R. Labs to protect the scientists as they developed the bomb. They fought a number of Shadow Demons and were about to be overwhelmed, when they suddenly got assistance from Jefferson Pierce/Black Lightning. Together, the three beat up the demons, and Barry assembled the shrink bomb, which Supergirl threw on Anti-Monitor, ending his threat forever.
====Battling Black Hole====
Frost could not understand why Cisco Ramon was upset; he explained that the whole timeline of Earth had been rewritten after the Anti-Monitor Crisis and he is wearing a shirt with the House of El symbol that he did not remembering owning. Frost thought that it was good that all the heroes were now on one Earth, but Cisco rebutted with a binder filled with all the villains that were also on one Earth. Frost wondered when Cisco had the time to accumulate such knowledge.
She then watched as Cisco and Nash argued about a crypto-circuit.
Frost tries to find Allegra a new boyfriend. They set up a date at Jitters but Allegra sees him with another woman and gets mad at Frost, but they make up and Allegra deicde befriends the man.
When Frost returned from visiting Ramsey Rosso, she found Chester P. Runk in S.T.A.R. Labs, asking her to play pinball with him; he was trying to avoid Barry and the mistake he had made while trying to improve Gideon. Frost explained to him that mistakes are "learnable moments" and every one of the members of Team Flash has almost killed Barry at one point, citing that even the janitor made the floor too slippery once. Chester explained why he didn't believe in second chances, but Frost corrected and encouraged him to use his genius to separate Barry's mind from Grodd's.
Frost responded when "Iris" called upon the Flash to come to Mercury Labs; there she found the Black Hole assassin Sunshine attempting to steal the Prismatic refractor. The two battled until the Flash intervened, which angered Frost because he was losing his speed and was asked not to fight. He suddenly collapsed; this left Frost vulnerable to attack because she turned her attention to him. Sunshine gave Frost a massive wound; as she stood over her opponent, Sunshine told Frost that her previous battle with Dr. Light made her famous in the organization. Joe West and the police arrived with guns drawn and caused Sunshine to withdraw, leaving Frost wounded and angry.
Frost summoned Ralph; while she waited for his arrival, she read Uncaged Desire. As Ralph gave her a "Dib-ploma", Frost listened to the advice he gave her about thinking that she was less than Caitlin and being scared of her mother; once she said that those feelings were gone, Frost "graduated" and thanked her life coach.
====Going north====
Still healing in Caitlin Snow's apartment, Frost watched as Cecile Horton, Allegra Garcia, and Nash Wells packed for her; Carla Tannhauser was coming to take her north to a facility there to accelerate her recovery. Nash fumbled around, which was annoying to Allegra, but Frost and Cecile encouraged him to continue with trying to connect with her. When Allegra asked if she could have one of her outfits, Frost allowed it. When Carla arrived, Frost corrected her about her less offensive new name and hugged her friends farewell.
Later, Carla complained that Frost was there; Carla wanted the more scientific personality of Caitlin in control to assist her in defining the baseline for the recovery process. Frost protested because she has all of Caitlin's memories and knowledge. This calmed Carla who realized that Frost was just as much her daughter as Caitlin, causing the two to work together and allowed Frost the ability to transform without harming herself.
As Caitlin bid Barry farewell as he told her about the death of Joseph Carver, Frost listened; Barry promised her individually that he will take her white-water rafting upon her return.
A few days later, Barry called Carla so she could update Frost and Caitlin on current events.
====War against Mirror Monarch====
Frost returned to Central City to help the Team Flash. She defrauded Eva McCulloch during one of her attacks on the Black Hole, while Barry and Cisco stole particles from her to reconstruct a device to release Iris from the Mirrorverse. During the fight, Frost was hit by Eva's blaster. She was taken to S.T.A.R. Labs where she was cured by an injection created by Barry. When she got up, Frost, Cisco and Barry saw Eva giving an interview to Arielle Atkins. Then Barry revealed that this was not the real Eva, it was a mirror duplicate created during the explosion of the particle accelerator. Barry then linked the video of Eva's death to Arielle's program, exposing the truth to the world. Frost then said that it was not a good idea to irritate the villain.
When Barry continued to change due to the artificial Speed Force, he decided to remove Iris from the Mirrorverse and leave Kamilla and Singh behind. Then Frost, Cisco and Allegra faced Barry. Barry defeated the other two but Frost used the Velocity X and soon became a speedster. They then run around the city and Frost tries to use both of her powers to stop him, but she is unbalanced and falls into a car. Barry says that her speedster time is running out and Frost says that she is not only a speedster, so she strikes a beam of lightning and ice that immobilizes Barry. Then Allegra appears and transports them to S.T.A.R. Labs using smoke bombs. But the quantum ball hits Cisco, who accidentally shoots Allegra, who hits Frost with ultraviolet energy and passes out.
Moments later, Frost woke up and Barry had brought Iris back and returned to normal. Team Flash along with the newcomers Chester and Wells came together to come up with a plan to stop Eva, who started kidnapping people in the city and replacing them with her clones. Frost and Cisco joined Barry in the final battle against Eva, who created clones of herself. Eva eventually gave up and went back to the Mirrorverse, and Wells went back to the past.
====Separated====
Somehow, shortly after the defeat of Mirror Monarch, Frost and Caitlin separated into two distinct entities; baffled, they turned to Cisco for answers, but he was justifyingly shocked. They asked Cisco what had happened but he was shocked, as were the other members of Team Flash. Caitlin eventually discovered that exposure to the Mirror Monarch's rays caused Frost's cells to replicate enough to create a new body, separating their telepathic connection so that they could no longer hear each other's thoughts. Cisco would use the Firestorm Matrix to put them back together, but Frost sabotaged the object, making Caitlin angry. Frost helped Barry and Cisco confront Psych, but they were defeated due to Psych using his fears against them. Frost later revealed that she wanted to live his own life.
Frost was painting in Caitlin's apartment when she appeared. Frost says that she had Matthew Norvock bring her things from storage. Frost is making the painting because there is an empty wall where she wants to place it; Caitlin retorts that great minds think alike and place the painting she brought on the wall. Frost inspects it and finds it lacking until she puts her own flare on it. When a wave of green energy hit Central City, Frost and Caitlin leave the apartment and go to S.T.A.R. Labs; the energy has changed Frost's outfit.
====Hunted by Kristen Kramer====
Frost was told by Cecile what charges were against her and told her to stay hidden in S.T.A.R. Labs, so Frost and Allegra exercised to pass the time. Chester told Frost that an ice-wielding criminal stole cargo from Ivo Labs and killed the truck driver; Chester also revealed that Kristen without proof blamed Frost. Frost decided to pursue the criminal herself and asked Allegra to cover for her if anyone questioned her whereabouts.
Frost went to Keystone City to an old job of hers to see if the bartender knew anything. Frost met Mark Blaine and found herself attracted to him. Meanwhile, Kristen appeared on television issuing a bounty for Frost's arrest. The patrons of the bar attacked Frost; she escaped with the help of Mark, who advised her to go to a warehouse, but when she got there, the warehouse was empty except for a laser which scanned Frost.
Frost learned that Caitlin was arrested because of facial recognition; Frost plotted to break her twin free, but Caitlin dissuaded her. 
 
Frost returned to Keystone City and confronted Mark, having realized that he was the criminal. Mark explained his origins and his desire to copy Frost's powers. The two fought. During the fight, Mark blinded Frost with his gauntlets; however, Frost won by stabbing herself and Mark, noting that since she is a meta, she can heal herself, while Mark, as human, could not and was in great pain. Allegra and the Flash arrived, with the Meta-human Task Force following. Frost decided, despite Allegra's protests, to surrender.
The prosecutor and Judge Tanaka are very lenient on Frost and will not seek jail time since the meta-human person made her who she is. They sentenced her to take the meta=human cure. But Frost declined and ask the judge, the prosecutor and the jury that she decided she will take life in prison without parole and take the punishment she deserves instead of taking the meta-human cure. The judge and the prosecutor give her what she wants and granted her life in prison without parole.
Days later, Caitlin, still sorrowful about Frost's imprisonment, told the story of Frost to Alexa Rivera to help her to understand how she can relate to Fuerza with the cerebral inhibitor. Later, Frost got a call from Caitlin.
Frost was visiting Carla when Caitlin called, revealing that Cisco Ramon was leaving to work for A.R.G.U.S. Frost sent a text wishing Cisco farewell. Frost found Mark, who had run away, but when she was going to stop him, he revealed that he had been forgiven.
====Fighting the Godspeed clones====
Due to becoming a state witness, Mark Blaine was wounded in the bar he worked as bartender. Frost made the group attacking him stop and persuaded Mark to accept going to S.T.A.R. Labs to be healed. Suddenly, an army of Godspeed clones attacked and Frost reluctantly gave Mark his cryogenic gauntlets. The two fought the clones, narrowly surviving the ordeal when the clones ran away to pursue the Flash. Later, Mark talked with Frost about the encounter and nearly kissed her. Then left after a drink shaker exploded.
====Armageddon====
====Dating Mark====
After making her 2022 New Years' revelation to forgive him, Frost began going on dates with Mark around the world. Among their destinations would be New Orleans in 2023.
Caitlin, now dating again, decided they should have a double date; however, it ended badly due to Caitlin mistreating Mark. Frost confronted Caitlin, telling her Mark had changed for her and that she needs to focus on her own relationship, since Marcus was waiting for Caitlin to give the sign she's ready.
====The Black Flame murders====
Frost helped Barry arrest Jaco Birch, whom they believed was burning people to death. While Frost believed him guilty like the rest of the team, Barry found proof Jaco was innocent. Frost helped keep volcanic activity caused by Jaco's emotional turmoil over his son being taken from him from damaging the city, while Jaco absorbed the heat after Barry cooled the lava below.
After Barry and Chester discovered that a meta was using black flames, S.T.A.R. Labs soon fell under attack by them. To everyone's shock, not only couldn't Frost put out the flames, but Cecile could sense the flames were sentient; the flames trick grieving people into being burned by appearing as the loved ones they miss. After Chester rejected the fake version of his dad, the flames vanished.
====Death====
Eventually, Frost became Hellfrost. Using a transmogrification to lure Deathstorm, she attacked him with her new powers. After the two fought throughout the city, Frost removed the quantum splicer from him and absorbed him into herself. Team Flash celebrated at first, but Frost was poisoned by absorbing Deathstorm. Barry carried her to S.T.A.R. Labs and worked with Caitlin to try saving her, but they only could wake her up as Frost briefly before she died. 
====Erased future====
In an erased future created by Eobard Thawne, he was the Flash and Barry was the Reverse-Flash. Along with Damien Darhk, the Reverse-Flash killed Ray Palmer, Nate Heywood, Sara Lance, and Cisco Ramon. In this timeline, Frost married Mark Blaine.
In 2031, Frost assisted Eobard and Iris' marriage ceremony. When Barry Allen crashed it, making the team angry. After Team Flash discovered that Barry worked with Damien Darhk, Frost and Mark had John Constantine put a protection spell against Darhk's black magic to fight him. When they encountered Darhk, he failed to use his black magic against them but could otherwise fight them due to his previous training in the League of Assassins. However, Ryan Choi could stop Damien Darhk from killing them.
==Personality==
<tabber>
|-|Present=
Worrying about her new-found, uncontrolled powers, Caitlin's emotions become heightened enough that she became a vindictive, angry and cruel individual, similar, but not identical to Frankie Kane's split personality disorder, also like Frankie, when affected by her powers, her eyes glow pale blue (while Frankie's glow pink) however, while Magenta tried to get rid of the Frankie persona altogether, Frost amplifies Caitlin's own fears, insecurities and bitterness. 
As Frost, she mocked Barry Allen by mentioning his most horrible failures, including the deaths of his parents, Nora Thompson, Henry Allen, Eddie Thawne and Ronnie Raymond, as well as revealing to Cisco Ramon that his brother, Dante Ramon was alive in the pre-Flashpoint timeline, before Barry changed it. She expressed bitterness over Barry only caring about himself and his own happy ending, while she was left broken.
Caitlin mocked Cisco by calling him pathetic for feeling sorry that he had to hurt her to save Barry. She openly blamed Barry for what's happened to her, yet admitted that she feels broken. She nearly killed Julian Albert and one of Alchemy's Acolytes, however, she was still unable to kill Barry, making her snap out of her anger, as she became horrified at what she almost did.
Once Frost was fully awakened due to Caitlin's temporary death and revival, she states that she doesn't want to be cured and wants Caitlin never to come back. She allies herself with Savitar after he reveals himself to her.
Frost went after Tracy Brand after Savitar promised that if she lives up to her name and murders Tracy, she could be a god, she arrived at CCU in her new outfit and attacked Barry and Cisco, but when Barry fought back with fire, she ran away, she then attacked Tracy for the second time outside Jitters and continuously formed an ice slide that she slid on for a while without any difficulty, she took advantage of the fact that Cisco would not hurt her and almost hit him with a blast that Barry took. She stabbed Barry in the leg so that he couldn't follow her and she left, claiming that this is her now.
Later, Frost kidnapped Joe West's girlfriend, Cecile Horton, outside of Joe's home and threatened to kill her if Joe and the team did not hand over Tracy to her and Savitar, later at the supposed exchange site, she claimed that killing Cecile would bring her no joy but Tracy's death at her hands would, when Barry tried to talk her out of it, she knew exactly what Barry was going to say, she and Cisco later faced off, and while she seemed calm at first, she later fought back as hard as she can and lost to him, Cisco managed to get a sample of her blood, which could be the key to making a cure for her. Before Cisco can take her, Savitar arrived and took her away.
Despite all this, while reluctantly working alongside her former allies, it was proven that she still has a strong attachment to her memories of working at S.T.A.R. Labs when she and Cisco reminisced about Ronnie losing his temper back when they were trying to build the particle accelerator, however, Frost also proved in this moment that thinking about who she used to be made her uncomfortable as she quickly, sullenly, stated that she didn't want to stay any longer than she had to. Her conflicted feelings about herself and her old allies were again emphasized when she told Team Flash she never loved them and left, only for the assertion to hurt her heart enough to cause the real Caitlin to emerge for a few seconds once she was out of the team's sight.
Despite Caitlin's continued allegiance to Savitar, she began displaying signs of regret and doubt in her betrayal, during the final confrontation of Team Flash and Savitar, Cisco's unceasing loyalty for Caitlin finally enabled Caitlin's true-self to become permanently restored and reconciled with her friends. At the same time, she felt lost, unsure of who she is now.
Six months after Savitar's defeat, Frost became stronger and eventually was able to regain control on various occasions, recently Frost's personality has become similar to Caitlin's, after Iris convinced Frost and Caitlin that they could co-exist they decided to be allies and not enemies, Frost has also become close with Team Flash, growing to appreciate their willingness to never give up on her despite her mistakes. She even assured Ralph Dibny that his friends will always be there for him when the latter briefly lost his confidence after failing a mission.
As of 2019, Frost has mellowed out. After being let out by Caitlin to develop her own tastes and hobbies, Frost was helped by Ralph to learn how to improve herself and learn to consider the feelings of others. She gained a fondness for homemade art after learning it represented the heart of its creator; something she sympathized with due to be her past of being repressed in Caitlin's psyche.
Post-Mirror Monarch, Frost was elated to discover her healing split her from Caitlin; allowing both them their individuality. Despite her preferred taste for punk fashion, the incident with the time displacement of the Still Force barbed her in a hippy look, Frost grew to like it and shopped at a thrift store for similar clothes.
|-|Erased future=
In an erased future where Savitar succeeded in murdering Iris West, by the time of the year 2024, Caitlin has become too far gone to the point; where she refuses to be called real name, as she prefers being called by her alias "Killer Frost", she becomes angry when individuals call her by her real name.
Despite Caitlin's insanity and cold nature, she is very observant, as she was able to realize that the Barry Allen that she was speaking to was the younger-self of her Barry; due to the look on his face, as the latter had not yet become emotionally broken, as his Iris was not dead yet. This future was later erased when Savitar killed H.R. instead of Iris; albeit by accident.
</tabber>
==Powers and abilities==
===Powers===
*Meta-human/Cryogenic physiology: After Caitlin Snow's father, Thomas Snow, discovered that she had the genetic marker for ALS, he used experimental cryogenic gene therapy on her to prevent the ALS from manifesting. The alterations Thomas had made to the treatment resulted in Caitlin developing a dual-personality (i.e. Killer Frost) and meta-human abilities soon after he treated her. Caitlin's Killer Frost persona, and the powers associated with her, remained dormant for 17 years (apart from a few brief episodes during her childhood), as several tests never showed signs of a meta-gene. Three years after the S.T.A.R. Labs particle accelerator explosion, Caitlin's powers finally emerged fully.
**: By from molecules to create gelid surroundings, Frost can generate dangerously low temperatures from her body, letting her freeze virtually anything. She can thus create sheets of ice, or shoot spearlike icicles at opponents. Frost can also create an ice slide and use her cryogenic powers to rapidly propel herself forward on the slide. Furthermore, her powers can reach such low levels that they can completely negate a speedster's healing powers and alternatively neutralize accelerated decomposing; by generating temperatures as low as -360 degrees, she proved able to shatter beings as powerful as the Black Flash. Frost often gestures when using her powers, but she can also freeze things by touching them (e.g. Frost can freeze people through a kiss) or being in the same vicinity. She was also able to freeze the light-based bullet from photon rifle in order to remove it from her body.
***: Frost is able to exhale cold mists with enough momentum to knock several people backwards and off their feet. She could also use this as a means to produce a thick and obscuring fog.
***: Frost is able to produce blasts of Ice and was able to attack many opponents with this ability and we seen this ability use throughout the series, especially when she fought Chillbliane and when she was fought off the guys in the bar who wanted to collect the bounty for her capture.
***: Using her thermokinetic cryokinesis, Frost can create constructs made of ice and icicles as shown in multiple occasions. During the Earth-X invasion, Frost was able to create ice swords to fight the Nazis and we also see Frost uses ice daggers as her main weapon to might opponents such as her fight with Cicada and her fight with Grace Gibbons, Frost was wielding two daggers and was able to go toe to toe with Grace but was overpowered. She can also turn her dagger into a sword and back in order to pierce her opponent through her own body.
***: Frost is able to heal injuries by filling the wounds with ice. As the wound heals, the ice will thaw until its fully healed, the ice will be melted by the time its healed. For example, when she used this ability to help with Cisco's hand after Cicada's dagger cutted him, closed up Cicada's chest wound after removing the dark matter shard, and when Joe was injured by Ramsey's zombies.
***: Frost's powers can also somewhat affect the weather around her, dropping the climate of the area and causing it to snow.
***: By generating cryogenic thrust, Frost was able to propel herself to the wall and then, to the ground to avoid herself from falling. Another instance is when we seen Frost propel herself into the air to fight her father's alter-ego, Icicle, by creating ice slides and she used this ability before when she took on The Flash while trying to kill Tracy Brand.
**: Frost is able to change her eye color whenever she uses her powers and her eye color transform to blue color. We seen this occur in multiple occasions; specifically when Frost started to emerge when she was with Catilin and when her emotions where heightened as Caitlin stated to Mick that whenever she is scared or annoyed, Frost appears and afterwards, Mick tried scaring Caitlin, causing Frost to emerge.
**: An added benefit to her powers, Frost's cells can withstand subzero temperatures, seeing as her body temperature was unaffected when Icicle decreased the temperature in a lab to absolute zero.
**: While accessing her powers, Frost's metabolic rate is augmented to offset cold tissue destruction, allowing her to regenerate from damage sustained on her body at a rate much faster than even a speedster; however, foreign matter must first be taken out to not impede the healing. After clinically dying from a combination of a seizure and her reopened impalement wound, she was immediately resuscitated into a stable and cognitive state while her wound seamlessly healed completely in seconds. Her healing is strong enough to withstand a photon blaster that was able to disintegrate a person in seconds. She was also able to quickly heal her self-induced wound when she stabbed herself with ice dagger.
**: Frost has shown remarkable durability, seeing as she has tolerated substantial amounts of physical distress; for example, she has survived being hurled into a car and electrical box by Vibe's concussive blasts without sustaining any serious injury. On one occasion, Frost stabbed herself through her stomach with her ice dagger in order to also stab Chillblaine, who had her in a headlock, with only minimal flinching.
====Former powers====
*: After Frost was removed from Caitlin by Clifford DeVoe, she briefly gained the ability to inhabit another body. She used this to briefly inhabit Cecile Horton's body. After she was restored to Caitlin, Frost seemingly lost this ability.
*: Frost and Caitlin were able to talk to each other whenever one of them was in control. After having a separate body, both Caitlin and Frost lost this power and now have to speak to each other through conventional means.
*Velocity X enhancement: After injecting herself with Velocity X, Frost gained the powers of a speedster. 
**: Like all speedsters, Frost could generate electricity from her body, which was blue in color. Due to having mastered her ice powers, (and possibly also from experiencing Flashtime before), she adapted to her newfound speed immediately. She was able to generate her remaining Velocity lightning on command, and unleashed a powerful lightning-enhanced cryo blast.
**: While her speed was not measured, she was able to keep up with and even outpace the Flash, who is able to run well over Mach 13, and was freshly recharged from the artificial Speed Force. Though she outpaced Flash due to having a similar familiarity with Central City and using her ice powers to slow him down, Flash was presumably running at his top speeds against her, noticeably exerting a lot of effort to phase and dodge her ice blasts.
**: Frost was incredibly agile, able to change direction immediately. She was able to make sharp turns on city streets while moving at super speed without sliding or losing her balance, and simultaneously use her ice powers, even on vertical surfaces, to create ice walls and ice blasts without slowing down.
**: Frost was able to get up with little to no injuries after being sent flying through the air and crashing into a car from an extremely high height. This was due to her already superhuman durability and her body adapting to the Velocity speed boost.
**: Frost's increased speed also augmented her reaction time, allowing her to react to danger and events far faster than a normal human.
**: Frost's body could handle the stresses of superhuman racing without noticeable distress, and her body's enhanced stamina allowed her to function much longer than a normal human without becoming tired or weak.
*Cold fusion enhancement: After Frost's powers got enhanced by the Mental Augmentation Chamber, she became more powerful than ever being capable of matching Deathstorm's abilities. Her cryokinetic abilities were restored by Caitlin briefly before dying, thus losing her new powers.
**Flight: Frost was able to fly at high speeds after her transformation.
**Pyrokinesis: Frost could manipulate and control fire created by extremely cold temperatures.
===Abilities===
*High-level intellect: While not quite as intelligent as her sister Caitlin, Frost is exceptionally intelligent. She is also very creative and adaptive especially in the field.
*Expert hand-to-hand combatant: To an unknown degree, during the six months in which she worked as an enforcer for Amunet Black, Frost developed a measure of sheer hand-to-hand combat skills. She once reversed an arm bar Norvock exerted upon her, slamming and pinning him painfully against a pinball machine. Frost also managed to hold her own against and even briefly injure Orlin Dwyer. Frost was able to fight on par against an older Grace Gibbons for a while, but was eventually overpowered. She was able to fight a zombified patient at a hospital with ice brass knuckles and later fight a group of zombies with Joe. By 2021, Frost’s fighting skills had improved significantly, likely from having received training from Barry as well as being out in the field more. She was able to swiftly defeat a bar full of criminals alongside Mark Blaine, and hold her own against Mark himself in their first encounter. In their second encounter she was able to overpower and defeat him. According to Mark Blaine, he revealed that both him and Frost won a wrestling tournament during their time together dating. 
**Skilled swordswoman: During the Earth-X invasion, Frost was able to create ice swords and take down multiple Nazis with ease.
**Expert knife-wielder: Frost uses ice daggers as her main weapon and has used them on multiple occasions in fights with her enemies. During a fight with Cicada, Frost used a dagger as a weapon; managing to injure him. On two separate occasions, Frost fought on par with Grace Gibbons, Frost wielding two daggers, for a while, but she was eventually overpowered.
*Artistic: As was first seen shortly before the Anti-Monitor Crisis, Frost struggles to expressing her emotions and imagination and it was evident when she attended Kamilla's art gallery and was unable to see the purpose of those paintings and referred to them as "garbage" and afterwards, she started to secretly express her imagination by starting to draw a photo of a ice queen having to be caught by Cisco and confessed that she is trying to express herself and afterwards, she started to express herself with art and started to paint and draw as shown when she was painting in Caitlin"s apartment.
*Peak of human physical condition: Frost is in top physical condition as shown as she is working out and staying active by catching bad guys and fighting meta-humans with Team Flash and also, we seen her working out in "Growing Pains", we see Allegra, her close friend, helping her workout as she is in S.T.A.R labs to avoid getting capture from Kristen Kramer.
*High tolerance of pain: During the six months in which she worked as an enforcer for Amunet Black and with the help with her healing ability, Frost probably learn how to tolerate pain as she was able to learn how to fight and her ability allow to heal quickly after she is injured, it make get use to pain and to survive more painful attacks by overpowered opponents. Also, we see Frost tolerable to pain as Caitlin kept pushing off her impulses when she started to emerge and we see her continuing to push her impulses until she was able to be surface.
====Alternate reality abilities====
*Peak of human physical condition: As a henchwoman of Superman, Frost was in top physical condition.
*Expert hand-to-hand combatant/Martial artist: Frost was a highly skilled hand-to-hand combatant and martial artist; she was able to overpower Oliver Queen with help from John Diggle when Oliver had lost his abilities.
===Weaknesses===
*Carbine: Frost has implied that, like to her Earth-2 counterpart, her powers have no effect on carbine.
*Power-dampening tech: Like most meta-humans, if Frost is wearing power-dampening cuffs; she can't use her powers. She can also be contained in a power-dampening cell.
*Doctor Light's photon rifle: When she was shot with Doctor Light's photon rifle, which was lethal to everything it touched, it created a wound that troubled Frost's accelerated healing, and after battling Sunshine the wound opened back up and worsened its effects.
*Abnormally high temperatures: Intense heat can apparently negate Frost's powers. However, the super speed she gained from Velocity X didn't negate her powers, since her thermogenic cryokinesis negated the heat that she generated.
**Flashtime: Frost can't properly access her powers in this state, since this causes friction between her atoms, which creates extreme heat under these circumstances. Put simply, she is not able to access her powers because Flashtime is an external source of speed, rather than an internal one that can be counterbalanced. 
**Nucleokinesis: It is likely that similar to her late Earth-2 counterpart, Frost will be severely affected by nuclear energy.
==Equipment==
===Original multiverse===
*Frost suit: Whilst fighting crime, Frost dons a protective suit for aid in her battles. The first suit was mainly for her evil persona and she eventually stopped wearing it after joining Team Flash, where she then wore a baby blue jacket with leather bottoms. After returning from her disappearance, Frost never gained an official suit at first, mainly just wearing black, until Cisco created a new, dark blue suit, similar to her first suit.
===New multiverse===
*Frost suit: Whilst fighting crime, Frost dons a protective suit for aid in her battles. After returning from her disappearance, Frost never gained an official suit at first, mainly just wearing black, until Cisco created a new, dark blue suit, similar to her first suit.
==Appearances==
===The Flash===
===Supergirl===
====Season 3====
* 
====Season 4====
*
===Arrow===
====Season 6====
*
====Season 7====
*
===DC's Legends of Tomorrow===
====Season 3====
*
====Season 5====
*
===Comics===
====EARTH-PRIME====
*
===Novels===
*
===The Chronicles of Cisco===
*
*
*
==Gallery==
Caitlin in the altered reality.png|Killer Frost in an Elseworld
Killer Frost erased future.png|Killer Frost in an erased future
===Promotional images ===
====The Flash====
=====Season 4=====
The Flash season 4 poster - Frost Warning!.png
===== Season 6 =====
File:The Flash season 6 poster - Speed. Force..png
File:The Flash season 6 poster - Stream the First 5 Episodes.png
===== Season 7 =====
File:The Flash season 7 poster - The Future Favors the Fast.png
File:The Flash Season 7 Finale Promotional Image.png
===== Season 8 =====
File:The Flash season 8 new poster.png
====Crisis on Infinite Earths====
Crisis on Infinite Earths poster - Their worlds will never be the same.png
===Concept artwork ===
====The Flash====
=====Season 3=====
Killer Frost (Caitlin Snow) concept art.png
===Merchandise===
==Trivia ==
*Killer Frost's original name was Khione.
*Frost and Caitlin have a close bond, so much so that they refer to each other as "sisters." This relationship would further be explored after having both been seperated in their own bodies like twins.
*Unlike Caitlin, Frost despises the color pink and hates wearing it, preferring to wear blue.
*According to Caitlin, both she and Frost enjoy the 1985 film The Breakfast Club. She stated that Killer Frost loves the character John Bender.
*She hates This is Us; having always shouted in Caitlin's head to turn off the show.
*According to Caitlin, Frost went to Burning Man in 2017 and made her deal with the hangover.
*Frost has a drink named after her at CC Jitters, the Killer Frost drink.
*By , both Frost and Caitlin can talk to each when either of them is in control, showing an acceptance that both them share the same body.
*Ralph Dibny affectionately calls her "Frosty".
*Frost may burn through the Velocity serum more slowly, due to her cryokinetic powers being able to keep her body cool.
* While Caitlin admittedly dresses "like a teacher", Frost favors a more punk/grunge look.
*Thanks to Ray Palmer providing a nanotech solution in 2019, Frost's eyes no longer glow and her voice doesn't echo either.
* Frost enjoys being her own entity; not having Caitlin in her head was the best thing about their split.
==Behind the scenes==
*Starting from , Killer Frost now goes by the name "Frost", just like in the comics when she became a hero.
**The dynamic between Frost and Caitlin is similar to that of Marvel characters Bruce Banner and his alter-ego, Hulk as they share a body. However, Banner and the Hulk hate each other while Caitlin and Frost love each other as sisters.
==References==
Category:Villains
Category:Vigilantes
Category:Iron Heights inmates
Category:Time travelers
Category:Characters with psychic powers
Category:Team Flash members
Category:Speedsters
Category:Allusions to the comics
Category:S.T.A.R. Labs Pipeline inmates
Category:Split personalities