Killerbelief/Other Killer

=== Backstory ===
In the Killertale timeline, after being recruited to kill, Sans was helping The Human and Chara to kill. When Sans went up to kill Papyrus, Papyrus reacted in shock and fear, attacking Sans blindly and killing him. This cured Sans' madness that had made him want to kill. He tried to tell Papyrus he was being forced to kill, ut didn't get the words out and died. Papyrus sobbed over Sans' death, ignoring The Human standing a few metres away. The Human was ready to kill Papyrus for interrupting the Genocide, but Chara was impressed with how Papyrus had shown to be when he killed Sans, and how much more powerful he was now with the LV he had earnt from it. Chara convinced Papyrus to take Sans place and help them kill everyone.
The plan was going well until Papyrus started to show regret for killing everyone. He told Chara he didn't want to kill anymore, that he just missed his brother. Chara told Papyrus about how before this timeline, The Human had killed everyone over and over hundreds of times before. This made Papyrus angry at The Human. He told Chara that now he wanted to kill The Human. Knowing how much more powerful Papyrus had become than The Human, Chara sided with Papyrus and they teamed against The Human.
=== Profile ===
==== Appearance ====
Papyrus' clothing looks somewhat the same, however it is a bit damaged from his encounter with Sans. Similar to Killer Sans, his eyes run with liquid hatred flowing out of them. He also has a red target-like soul on his chest.
==== Personality ====
During the killing, he wasn't paying much attention to what was really happening due to the madness Chara inflicted onto him. He was mindlessly slaughtering everyone until he began to regain consciousness of who he was and what he was doing. After turning against The Human, he is half-sane and regrets killing half of everyone.
=== Battle ===
There is no Killerbelief battle yet, but this is what my interpretation of it would be.
In Phase one, he uses difficult attacks, thinking The Human will die quickly.
In Phase two, after being hit once, he becomes enraged and will use stronger attacks that last longer, only letting The Human have their turn once. Chara will help them during this phase.
In Phase three, his power increases significantly, joined by Killer Sans and Undyne. Chara lingers in the background, watching Papyrus.
In Phase four, Papyrus goes against Chara and gives The Human another chance, saying they can both stop killing.
In Phase five, Papyrus gets hit by a betrayal attack, which depletes his HP completely. However, Chara uses the LV and determination they have earnt as a last-second save for Papyrus, which completely restores his HP and increases his ATK and DEF by a lot. This phase lasts for a few minutes in which the player does not get a turn. At the end, The Human will finally lay another hit on Papyrus, finally killing him and Chara.
=== Abilities ===
Real Knife
Papyrus uses a Real Knife, lengthened into a Machete through magic. Due to this lengthening and his LV, it now deals 999 DMG.
Sharp Bones
These bones deal more DMG and can cause bleeding.
Memory summoning
Papyrus can summon Killer Sans and Undyne in Phase 3.
Killer Blaster
Like Sans, Papyrus has one giant blaster that kills instantly when someone is proving difficult to kill.
Chara
After having his HP depleted, Chara can instantly heal Papyrus and increase his ATK and DEF through determination, however they only manage to use this once because it has a long cooldown time.
=== Relationships ===
Sans (Deceased)
After accidentally killing Sans in self defense, Papyrus was incredibly sad because of his death and it being Papyrus' fault. Eventually, because of Chara, he got over it and didn't think about him again until he started coming to his senses.
Undyne (Deceased)
Undyne was Papyrus's mentor, familiar and also friend. She saw Papyrus and told him about Monsters being killed by a Human and someone else, then found out it was Papyrus. Papyrus killed Undyne without a word because he had not started coming to his senses yet.
Chara
Papyrus during his madness thought of Chara only as a helper. After showing regret, he started to think of them as more of a friend helping them to kill The Human. In Phase 4, he betrays Chara in a way by sparing The Human. If Papyrus is spared, Chara disappears from Papyrus' mind. If Papyrus is attacked, Papyrus then sees Chara truly as a friend who brought them from the brink of death and is helping him one more time, despite the betrayal.