Breen The Breen were a reclusive , powerful , and war like humanoid race , native to the planet in the Alpha Quadrant . Shrouded in mystery , the Breen were also one of the most underestimated races inhabiting that quadrant of space . History and politics . Historically , the Klingon s were among the first to discover that the Breen didn ' t tolerate incursions into their space . During the Klingon Second Empire , Chancellor Mow ' ga ordered an entire fleet of Klingon warships to invade and conquer the Breen homeworld . The fleet never returned and was never heard from again . ( ) Breen privateer s during the 24th century often conducted indiscriminate raid s against other Alpha Quadrant species . This included the Breen attack and capture of a Cardassian transport , the " Ravinok " , in 2366 . The survivors of that attack were used for slave labor in Breen - operated dilithium mines on Dozaria . ( ) Even by the 24th century , though , much was still unknown about the Breen and their government , known as the Breen Confederacy . ( ) The Federation had limited knowledge of the Breen , however , and was aware of Breen outpost s located in Sector 97 in 2368 . That same year , Starfleet fear ed the Breen might have attacked the science vessel there . ( ) In 2370 , the Breen participated in a palio held at Federation space station Deep Space 3 , during which the Ferengi attempted to bribe a Breen pilot into deliberately losing the race . ( ) In 2371 , evidence seemed to briefly indicate that the Breen may have attacked another Federation space station , the Amargosa observatory , though the true aggressors were , moments later , determined to have been Romulan s . ( ) Nevertheless , by about this point , the Breen were considered one of the most warlike species known to the Federation . ( ) In 2372 , the Breen captors on Dozaria were located by Kira Nerys and Dukat . Dukat stated that he didn ' t approve of what the Breen were doing , by employing the survivors of the " Ravinok " as slaves , but did " admire their ingenuity . " The Breen guard s were ambushed by him and Kira , so that they could free one of the Breen ' s prisoners : Dukat ' s daughter , Tora Ziyal . ( ) Later that year , Breen privateers raided the Bajoran colony of Free Haven ; they were , however , successfully driven away by the . ( ) By 2373 , the Cardassian Union maintained an embassy on the Breen homeworld . ( ) The same year , Breen settlements on Portas V , near the Demilitarized Zone , dealt with the Maquis , supplying them with cold - storage unit s . ( ) Whereas a Breen individual was held captive by the Dominion at Internment Camp 371 in 2373 ( before killing a couple of Jem ' Hadar guards there and , in retaliation , being shot to death in that year ) , other species like the Ferengi had developed closer ties with the Breen by the late 24th century , as both species conducted trade negotiations in 2373 . ( ) Once , in 2374 , Ferengi engineer Rom referred to the Breen as one of the top three toughest mercenary species that he and his brother , Quark , could find ( the others being Klingons and Nausicaan s ) . Rom suggested including the Breen in a commando team which would be sent to rescue his and Quark ' s mother , Ishka , who was being held prisoner by the Dominion , but Quark declined the Breen ' s involvement , opting for the rescue operation to be attempted by Ferengi only . Ishka ' s captor , Vorta clone Yelgrun , considered Breen annoying , though not as much as Ferengi . ( ) It was noted by Ezri Dax in 2375 , when she and Worf were captured by the Breen on the planet Goralis , that they were a long way from Breen space . ( ) The Breen interrogated Worf and Dax , but the information which the pair consequently provided was somewhat confusing . ( ) In Worf ' s opinion , the Breen were not only dangerous but also had no honor . ( ) Alliance with the Dominion . Meanwhile , Breen representative Thot Gor had been extensively conversing over subspace with the Female Changeling , the leader of the Dominion , in discussions that she found to be particularly productive . ( ) The Breen were of no personal interest to her other than the military advantage they could provide against the Federation Alliance in the Dominion War , in which the Female Changeling was determined to lead the Dominion to victory . ( ) In 2375 , the Breen moved from a policy of low - level hostilities toward most other major powers to one of open warfare when they allied themselves with the Dominion as reinforcements . ( ) To mark the historic moment when the two parties first met in person , the Breen presented Worf and Ezri Dax as gift s to the Dominion . ( ) According to the terms of the alliance , the Breen Confederacy received several planets in the Cardassian Union as compensation for joining the war . Despite being welcomed by the Female Changeling and Vorta leader Weyoun , the Breen were mistrusted by the leader of the Cardassian Union , Legate Damar , who was frustrated by the details of their treaty with the Dominion . For instance , the Breen were thereafter allowed unlimited access to the Dominion ' s database , whereas Damar was annoyed at them being permitted to use it at all . His frustration over how the Breen were being received led Damar to begin a Cardassian rebellion against the Dominion and enable Ezri Dax and Worf to escape back to Federation space . ( ) Even for the Cardassian rebels , the addition of the Breen made the Dominion more formidable than ever . ( ) Shortly after joining with the Dominion , the Breen attacked Earth , assaulting Starfleet Headquarters and destroying the nearby Golden Gate Bridge . Most of the Breen attack force was destroyed by Starfleet , though the majority of the damage on Earth had been done by that time . The Breen were so secretive that the only thing Starfleet knew about them , up to then , was that they were a race of warriors , an aspect of the Breen which the Klingons learned in light of their attack on Earth , as not even the Klingons had ever attempted such a strike . Even Weyoun and Damar considered the Breen to be " full of surprises , " albeit for different reasons . ( ) A short time later , the Breen assisted Dominion forces in breaking the lines at Chin ' toka , launching a counteroffensive against the Federation Alliance there and breaking through in two places . To Rom ' s son , Starfleet Ensign Nog , the Breen now seemed unstoppable , though Worf refuted this opinion , believing that no foe was overcomeable . A major battle which followed , known as the Second Battle of Chin ' toka , was won by the Dominion thanks to a unique Breen device , a kind of energy dampening weapon which could completely drain all the main power systems of a starship . Those vessels which were destroyed by the Breen weapon during the battle included the USS " Defiant " . ( ) In fact , the only ship immune to the weapon was a Klingon Bird - of - Prey , the , which serendipitously survived thanks to an adjustment the chief engineer had made to the ship ' s tritium intermix in the warp core . ( ) Under orders from the Female Changeling , the Breen allowed escape pod s to carry Federation survivors to safety , and the Breen were thanked for the decisive part they had served in the battle . ( ) Both this defeat and the Breen ' s devastating assault on Earth dealt a huge blow to the Federation Alliance ' s morale . ( ) The Breen were also being used to defend numerous Dominion facilities . ( ) Breen engineers were assigned to begin retrofit ting Dominion ships with the energy dampening weapon . The engineers were instructed to accelerate the installation program , an order that had been sent from the Female Changeling and was relayed to the engineers by Thot Pran , a Breen official . According to one report ( from Kelvas V ) , the Breen would start installing the weapon on Jem ' Hadar fighter s within a week . ( ) Although the Klingon fleet was able to make the needed adjustments against the weapon , the Federation and the Romulans were still unable to defend against the Breen . ( ) Hence , the Breen were prevented from acquiring final victory for the Dominion only because the Klingon vessels were present . ( ) When the Federation finally did create a defense against the energy dampening weapon , they forced the Dominion fleet to retreat . Thot Pran expressed an extreme distaste for surrender , and required the reassurance of the Female Changeling that , instead of surrendering , they were actually regrouping and attempting to redouble their shipbuilding and replenishment efforts . ( ) With the necessary countermeasures against the Breen ' s energy dampening weapon obtained , the Federation Alliance was able to go on the offensive once again , choosing to try to invade Cardassia Prime itself . In hopes of raising the Breen ' s will to fight , the Female Changeling offered them control of Earth and Romulus if they succeeded in winning the battle . However , she then told Weyoun this was merely a political promise , designed just as motivation . While every Breen soldier on Cardassia was participating in a concerted search for Damar , the Breen , in the interest of maintaining their alliance with the Dominion , were positioned ahead of the Jem ' Hadar by the Female Changeling , under pressure from Thot Pran . During the ensuing Battle of Cardassia , the Breen were still able to inflict major casualties on the allies , even without the use of their energy dampening weapon . Up to a third of the allies ' entire fleet was destroyed during the battle , including the Romulan flagship , even though sabotage by the Cardassian rebellion resulted in the Dominion fleet being out of contact with their headquarters until midway through the battle . The Breen continued to fight for the Dominion until the end of the war , demonstrating a willingness to die for the cause which matched that of the Jem ' Hadar . However , when the Cardassian forces switched sides mid - battle , the Dominion and Breen were forced to withdraw to Cardassia Prime . The Breen leaders left Dominion Headquarters in order to fight on the front line s , and both Damar and Weyoun were shot to death shortly thereafter . At the Dominion defense perimeter in orbit of the planet , the Breen were targeted by the Klingons , in a three - prong attack that saw the Romulans and Starfleet focus on other targets . After Odo convinced the Female Changeling to surrender , the Breen and their allies stood down , finally bringing an end to the Dominion War . As collaborators of the Dominion , the Breen leaders were present during the signing of the Treaty of Bajor . ( ) Physiology . The Breen had no blood or other liquid circulatory system . ( ) The species was one of many whose thoughts and emotion s were not detectable by empathic species , such as Betazoid s . ( ) The Breen had at least one gender : male . ( , " et al . " ) The Breen constantly wore refrigeration suit s . According to Worf , no outsider had ever seen what a Breen looked like under their refrigeration suits and lived . ( ) Even shortly before the Dominion War was concluded , their appearance remained so completely unknown to their allies that Weyoun could not avoid wondering what the Breen looked like . ( ) Ezri Dax once had a dream that featured a male Breen taking off his helmet to reveal he was actually Julian Bashir , and the Female Changeling , on one occasion , commented to Weyoun that under Thot Pran ' s helmet was " a braver man than you . " ( ) Worf firmly concluded that the species didn ' t have claw s , although Ezri Dax wasn ' t sure of this belief . She , on the other hand , speculated that the Breen might be covered in fur , due to their home planet purportedly having a remarkably cold climate . ( ) Dukat expected Dozaria ' s climate would be about fifty degrees too hot for the species , so he expressed extreme surprise at finding Breen guards on that planet . ( ) However , while the intelligence report s available to Cardassian and Dominion leaders during the Dominion War reported their homeworld to be a frozen wasteland , Weyoun remarked ( in his capacity as a diplomat ) that the planet was really " quite comfortable . " ( ) Breen appeared physically more resilient than most humanoids . When Worf struck a Breen , the Breen proceeded to incapacitate Worf with a neural truncheon , seemingly oblivious to the assault . ( ) Society and culture . The Breen commonly endured pregnancy at a young age . ( ) They entertained and taught their offspring with nursery rhyme s . of a Breen nursery rhyme was made up of a heterophonic , five - line verse with an alternating tetrameter and pentameter structure . These were nonsensical phrases , strung together because they rhymed ( at least to the Breen ) . Breen music which accompanied this nursery rhyme was written on a Lyxian scale . ( ) Based on how algae paste tasted , Ezri Dax humorously speculated that the Breen were " horrible cook s . " ( ) The Breen rank structure included the title thot , which was implied to be greater than that of a Cardassian legate . ( ) Other Breen worked as engineers , including at least four at the Kelvas repair facility . ( ) Treatment of prisoners . The Breen were known to use slave labor , and at least some of these slaves were captured in raids on other species . When the Breen were using Bajoran slaves to mine dilithium ore , there were always at least eight guards within the mines . ( ) The Breen were very prudent when dealing with prisoners . When capturing prisoners , the Breen typically stun ned them from long range with their disruptor s , rather than approaching them and risking close combat . When Worf and Ezri Dax were discovered by the Breen on Goralis while sleep ing , the Breen used this technique to subdue them . The Breen also fed their prisoners a diet of algae paste . ( ) Aboard starships , the Breen typically sent in three guards at a time when they wished to remove a single prisoner from a cell that was being shared with other prisoners . Although Worf made various attempts at escape , they all failed , including an attempt to persuade the Breen guards that Ezri was sick , as well as an attempt to short - circuit the door of their cell . When Worf attempted to attack the Breen guards , they used a type of neural truncheon to paralyze him . Even after he fell to the ground , partially paralyzed , two Breen guards continued to use the truncheons on him to ensure he would not get back up , before two guards removed Ezri from the cell . ( ) In another incident , Worf simply showed signs of anger towards Weyoun and was again shocked by the neural truncheon . ( ) On the other hand , a holographic Breen , enhanced by the Hirogen and participating in Iden ' s Rebellion of 2377 , once helped a holographic Romulan restrain B ' Elanna Torres , but did so in a way that was relatively very careful , taking Torres by the arm to a position where a force field could be activated around her . ( ) To extract information from captives , the Breen used cortical implant s , despite the fact that they caused extreme mental and physical side effects to the recipient , including severe pain and hallucination s . ( ) Language . See : Breen language Science and technology . Given that most known humanoid species lived on class M planets with an average temperature far above the supposed temperature of Breen , the Breen were largely thought to have had to develop refrigeration suits in order to co - exist with others . However , if the Breen homeworld was temperate , as stated by Weyoun , then their reason for wearing environmental suit s , if they were environmental suits at all , was much more mysterious . ( ) The Breen were known for their knowledge of sophisticated cold - storage units , summed up in a statement Captain Benjamin Sisko once made : " " If anyone knows how to keep things cold , it ' s the Breen . " " ( ) During the 2360s , the Breen were known for their development of organic technology , which they employed in the construction of their spacecraft . ( ) Some of their vessels were even believed to be fitted with cloaking device s . ( ) During the mid - 2370s , Breen warship s utilized energy dampening weapons . ( , " et al . " ) The expediency with which the Breen could mobilize large fleets of ships surprised Damar . ( ) The Breen ' s piloting skills likewise impressed Nog . ( ) The Breen were known to use type 3 disruptor s , in common with the Romulans and Klingons . ( ) The Breen also manufactured a portable hand - held cannon , the CRM 114 , which was designed to target moving objects and surface emplacements . It was among numerous weapons dealt by Ferengi arms dealer in the mid - 2370s . ( ) A holographic facsimile of a pistol was almost used by the holographic Breen in Iden ' s Rebellion , moments prior to that Breen being deactivated . ( ) The Breen made use of memory - probing technology , in the form of cortical implants , and neural truncheons for subduing prisoners . ( ) Mirror universe . In the mirror universe , Intendant once told Benjamin Sisko that Breen icicle s were warmer than Professor . ( ) Appendices . Background information . In the final draft scripts of and , the term " Breen " was listed in the pronunciation guide , phonetically notated " BREEN " . Some of the actors and stunt performers to have worn the Breen costumes are Cathy DeBuono , Todd Slayton , Max Omega , Wade Kelly , Dennis Madalone , and Tom Morga . Initial references . Ira Steven Behr once described the Breen , considering the references to them on , as " sort of a running joke " in TNG . ( " " , p . 277 ) Marco Palmieri similarly reasoned that contemplating all the canonical facts about Breen biology is " " enough to give the impression that as each new tidbit about the Breen was being conceived , little thought was given to the composite picture being created . And it may well be that this is exactly how the Breen started . " " ( ) The first evidence of the Breen was in the TNG Season 4 episode , in which Data , during a meeting of the ' s senior staff , mentions the Breen as one of " many races that are not empathically detectable . " Both in that episode and the next installment to mention the Breen , TNG Season 5 ' s , the Breen are cited as a possible culprit by Data , firstly in regard to Deanna Troi losing her empathic Betazoid abilities and secondly concerning the destruction of the SS " Vico " . In both cases , the Breen are found not to be the cause . Jeri Taylor proposed exploring the Breen in an ultimately abandoned season finalé that would have ended TNG Season 6 . In a memo which initially outlined the story ( a document which was sent from Taylor to Michael Piller on ) , the Breen were described as " a bellicose , brutal species who inhabit a distant but expanding empire . " In the narrative , a Breen delegation was to be met and escorted to Earth by the " Enterprise " - D , formally establishing diplomatic relations between the Breen and the Federation . Although the Federation had long been happy that the Breen lived far from Federation space and had been expecting the species to be adversarial , the Breen had recently made the first tentative step toward establishing ties with the Federation . The unpleasantness of the species , however , became apparent to the " Enterprise " - D crew when the two groups met . They arranged an initial joint mission , whereby Starfleet scientists were sent on a Breen vessel to investigate a recently discovered phenomenon , but the ship suddenly vanished without explanation . In response , the Breen volatilely accused the " Enterprise " of being duplicitously responsible for the ship ' s disappearance , but the " Enterprise " then discovered the Breen ship , caught in an anomaly , and attempted to rescue it , the Starfleet crew jeopardizing their own vessel in the process . Jeri Taylor was of the opinion that using the story as an opportunity to introduce the Breen as a new adversary " would infuse new energy into the 7th season . " In a revised version of the plot ( relayed by Taylor to Piller in a memo dated ) , she suggested that the Breen delegation meet with the starship " " , under Riker ' s command , rather than the " Enterprise " , though the latter still undertook the rescue attempt ( much to Riker ' s chagrin ) . When Riker opted to go to the aid of the " Enterprise " while it was endangered due to the anomaly , the Breen were unsettled by this decision . The volatile Breen were thereafter encountered by Captain Picard , when he came aboard the " Indiana " , moments before he was blown out of the ship , through a rupture in its hull , and out into space . Although the Breen and their involvement in the palio on DS3 are discussed as essentially smalltalk between Picard and Vice Admiral Marcus Holt in TNG Season 7 entry , the Breen ' s function as suspects was not finished . They weren ' t referenced at all in the first draft script of , despite being mentioned on - screen in the final version of that film , wherein Riker cites them as potentially responsible for the attack on the Amargosa observatory , though this is later determined not to have been the case . First appearance . When the DS9 writing staff required a villain for DS9 Season 4 episode " Indiscretion " , an opportunity to physically depict the Breen presented itself . " " We just struck on the idea to use the Breen , " " stated Robert Hewitt Wolfe . ( " " , p . 277 ) In the script of " Indiscretion " , the Breen were described as " " tall , well - armed humanoids in dark , armored pressure suits which protect them from " [ . . . ] " harsh atmosphere . " " The hidden manner in which the Breen were portrayed – fully clothed , wearing masks and helmets – was influenced by the fact " Indiscretion " came very soon after episodes which featured large numbers of Klingons and Jem ' Hadar ( namely , and respectively ) . " " I wasn ' t really in the mood to come up with a new alien race , " " explained Ira Steven Behr . " " So I said , ' Let ' s not see them . Let ' s just put them in costume because they normally live in the cold . " " ( " " , p . 277 ) An additional motive for Behr deciding that the Breen should appear in fully enclosed costumes was that this would cut down on make - up expenses . ( " " , issue 69 , p . 17 ) When the Breen helmets were being designed for " Indiscretion " , it was decided that they would give viewers the suggestion of a snout , like that of an . ( " " , p . 277 ) Terry J . Erdmann recalled about the Breen , " " They were never supposed to be important at all , so when the wardrobe department first made Breen costumes , they were kind of simple ; they just made a mask and put them on some guys who were going to stand in the background . " " ( ) Interim . The word " Breen " was listed in the pronunciation guide for the final draft script of DS9 Season 5 installment , which noted that it " rhymes with ' green ' . " However , the term wasn ' t actually used anywhere else in that teleplay . The Breen were not referenced in the first draft script of fifth season outing , despite the species being talked about in the final version of that episode . As of the start of DS9 Season 6 , the show ' s writing staff didn ' t have any plans to feature the Breen in the series . However , Ronald D . Moore didn ' t rule out such a possibility , remarking , " " We could explore them in the future . " " Return . At the start of a nine - episode arc that was designed to bring an end to " Star Trek : Deep Space Nine " , the Breen were brought into the Dominion War by the show ' s writers . Thus , the species went from having been used only " a handful of times " prior to DS9 Season 7 to becoming " major players " ( as worded by First Assistant Director B . C . Cameron ) in the first of those installments , . Their introduction into the conflict was motivated by the writers feeling sure that the Breen would heighten the stakes of the war . ( " " , pp . 685 & 702 ) Christopher L . Bennett observed that there was probably an additional reason why the Breen were introduced into the Dominion War . " " I think the main reason for bringing in the Breen , " " he said , " " was to establish that the Dominion saw Cardassia as disposable – not the partners they ' d promised , but just a stepping - stone toward their conquest of the quadrant , to be tossed aside as soon as they ' d outlived their usefulness ( if you ' ll pardon the mixed metaphor ) . It was a motivator for Damar ' s – and Cardassia ' s – journey toward rebellion . " " As the writing staff didn ' t have the entire war worked out when they brought the Breen into it , they were uncertain how much would ultimately be learned about the Breen in the series . ( " " , p . 685 ) Nonetheless , the Breen ended up as the last major villains to be introduced in DS9 . Also , the fact that so little had been established about them , thus far , gave Designer John Eaves a feeling of particular freeness while designing the Breen warship , for " Penumbra " . ( " " , issue 69 , pp . 10 & 11 ) The DS9 writing staff wanted to make the Breen seem highly mysterious . " " We wanted to give these guys something special , " " commented Ira Steven Behr . " " I couldn ' t make them the toughest guys in the galaxy – that ' s the Jem ' Hadar . Or the most arrogant guys – that ' s the Cardassians . Or the most untrustworthy guys – that ' s the Vorta . So we decided to make them the most " mysterious " guys in the galaxy , with voices that really grate on the audience . " " Behr has also said that the Breen ' s distinctive , scratchy voice , which was first spoken in , was inspired by the guitar feedback on ' s album . ( " " , p . 703 ) When they decided to bring the Breen back , DS9 ' s creative staff had to reuse the same costumes which had already been created for the species . " " One day , the wardrobe department gets this call . ' Guess what ? We ' re going to use the Breen , " " Terry J . Erdmann related . " " Well , those masks that those poor actors are wearing have a long bill on the front , with only a tiny hole at the end for them to breathe . They snap on to the back , so they are difficult to put on and off , and the eye holes were in the wrong place , so they really couldn ' t see . But these almost unusable costumes were established , so they were stuck with them . " " ( ) Not only did the costumes hamper breathing and seeing ( the latter of which caused background extra Wade Kelly , when B . C . Cameron asked him to walk across a room , to repeatedly stumble noisily on set , during production on ) , but wearing them also brought a host of other problems too . B . C . Cameron pointed out , " " They ' re wearing big , clumsy boots , and their outfits are layered like an armadillo , making it very hard for them to move . " " Regarding the difficulties of using the Breen helmets , Steve Oster explained , " " They ' re held together with magnets and they fall off any time someone bumps them . And before we redesigned them , the switches for the little blinky lights were on the inside of the helmet . " " This meant the helmets had to be removed from the actors every time the lights needed to be turned on . " " And for some reason we never did figure out , " " continued Oster , " " the nine - volt batteries only lasted minutes before they burned out . " " Thot Gor actor Todd Slayton considered " the biggest problem with the Breen mask " was the tiny hole for breathing , which he estimated was about eight inches away from the wearer ' s nose . He also noted that the viewing lens in the mask often steamed up quite quickly . ( " " , p . 702 ) During the course of writing the Dominion War , the DS9 writers were very intent on establishing the Breen as extremely formidable , tough aliens . This inspired the introduction of the Breen energy dampening weapon and the destruction of the USS " Defiant " , in . ( " " , p . 693 ) The final Breen to be depicted ( both in the show ' s chronology and production - wise ) was the holographic individual in . The final draft script of " Flesh and Blood , Part I " called for multiple holographic Breen to appear in the episode , although only one is present in the final version . Uncertainties and trivia . Ultimately , it was never made clear how the Breen actually looked , inside their costumes . Whereas First Assistant Director Lou Race " always " suspected the Breen looked similar to ( owing to the beak - like part of their helmets ) , Make - Up Supervisor Michael Westmore admitted that he wasn ' t really sure how they looked . However , he also reflected , " " I actually had an unused head in the lab that would have been great . I thought we could put a little bit of a snout onto it , so we could justify the snout on the helmet . But we never had the opportunity to show one of them . " " ( " " , pp . 701 - 702 ) It was also left unclear whether anyone had ever seen a Breen and survived the experience . In " ' Til Death Do Us Part " , Worf states , " " No one has ever seen " [ a Breen ] " and lived to speak of it . " " However , " Indiscretion " implies that Kira and Dukat must have gotten a look at a pair of Breen whose uniforms they stole . Compounding the continuity problem , Kira is implied as having dispatched another Breen , again for his uniform , in DS9 series finalé . In hindsight , Ronald D . Moore regarded this continuity glitch as one of numerous frustrating details that , due to their sheer quantity , the creative team hadn ' t managed to keep track of . On the other hand , Ira Steven Behr proposed an in - universe explanation , saying , " " There ' s " nothing " in those helmets . I don ' t think there ' s a guy in there , which is something we never got around to saying . " " After a pause , he added , " " Or maybe there ' s a little slug , some tiny little creature in there . I never wanted them to be humanoid in any way . " " ( " " , p . 702 ) Despite this , not only did the aforementioned script of " Indiscretion " regard the Breen as " humanoid " but so do the reference works and " " ( p . 35 ) as well as the StarTrek . com database entry about the species . The model for the Breen helmet closely resembles a that wore to ' s Palace in " " . Reception . The writers of " " ( issue 69 , pp . 16 & 17 ) approved of the Breen . They regarded them as " vitally important to the Dominion War " and further remarked , " " Despite the hazards of the costume , the Breen proved a tough and formidable adversary that ratcheted up the threat to the Federation in the final months of the Dominion War . Without them , the final story arc would not have been so tense and compelling . " " Marco Palmieri wrote , " " You have to hand it to the Breen : For a civilization that started out as a sometimes - mentioned but never seen running gag on " The Next Generation " , they eventually came incredibly close to handing the Founder s a decisive victory in the Dominion War . Along the way , the Breen not only destroyed the Starship " Defiant " , they succeeded where no other enemy empire had before : attacking Starfleet Headquarters on Earth . Even the Klingons had reason to fear them " [ . . . ] [ considering ] " an Imperial fleet sent to conquer the Breen homeworld was never heard from again . That ' s not a bad résumé as " Star Trek " villains go . " " ( ) Apocrypha . Decipher ' s Role Playing Game supplement " " explained the discrepancy over whether anyone had seen a Breen and lived by establishing that the Breen disintegrate upon exposure to atmosphere . The video game " " features Breen as one of the people groups which players can assume the role of . Of the three types of commanders available – attack , defense , and movement – the Breen only have defense ( 2 ) and movement ( 1 ) available . In " Star Trek Online " , the Breen were the main antagonists in a short episode arc . During the arc , the Breen invaded space , hoping to acquire technology . In the novel " Zero Sum Game " , the Breen are revealed to be comprised of several different species , with " Breen " as the name of a society , rather than a single species . The primary reason for this is to judge individuals on their skills and abilities rather than their physical appearance . In reality , however , this approach was taken by " Zero Sum Game " author David Mack because he believed that trying to reconcile all the canonical " facts " about the Breen ' s physiology would otherwise be impossible , as he thought there were too many discrepancies . ( ) Among the species in the Breen Confederacy mentioned in " Zero Sum Game " , only four were mentioned by name and described in some detail , and an additional fifth species was described in the novel " Plagues of Night " . Two more species are named in the novels " Disavowed " and " The Hall of Heroes " . They include :