Castor: Let's be honest, Arudin, you're more evil than most of the villains we face. Khagoth: Meaner too. Arudin: I am not evil! I am just... colorfully pragmatic! Khagoth: Whatever. Castor: We're going to bed, Captain Evil.
— Dungeoncrawl Inc.
Just because the main characters are fighting to oust the Big Baddoesn't mean they're heroes... at least, not all of them.
In a team composed of good members, there will often be one Token Evil Teammate. Narratively, this character can serve as an distinct and amoral foil to his more strait-laced colleagues. If the Heroes start putting Honor Before Reason, the Token Evil will often remind them that sometimes unpleasant methods are needed to save the world.
These characters are often Played for Laughs as the Heroic Comedic Sociopath. A lot of the humor they provide is of the Crosses the Line Twice variety, doing obscenely wrong things because it's shocking and unexpected, as well as a form of escapism. On the other side of the fence, a very serious character that fills this role might see it as Dirty Business, and do what they have to on behalf of the hero.
Despite the name, the Token Evil Teammate has a lot of leeway as to his Character Alignment. There are many kinds of Anti-Heroes, Anti-Villains and yes, outright Villains who can fill this role. Regardless of character type, the mainstays of this role are usually: snarkiness, jerkiness, violence, and a tendency to become the Butt Monkey for their behavior. It should also be mentioned that "treachery" was not on that list. The thing with the Token Evil Teammate is that evil does not mean incapable of friendship. While they are usually out for themselves first, they will often have reasons to stay loyal to their team as a whole, or at least individual members.
Sometimes they'll (very) begrudgingly admit that they like their teammates, or at least find them less intolerable than they say, and frequently they find their association either lucrative, entertaining, or even enjoyable. If it's pointed out by somebody that they're not as bad as they make themselves out to be though, they'll generally tell them to shut up, or to take it back. For extra points, this can be done in either a very cold, aloof or very rude and loud way.
If they do betray their teammates, expect The Captain to tighten the Morality Chain or Restraining Bolt and use various threats like Death Glares to bring them back in line. Why don't they kill him or at least kick him out? Because sometimes you just need the firepower, and they can "do more good than malice" (or at least less harm) on the good guys' side than dead or cut loose. Kind of like controlling a brush fire to good ends.
Some variations include:
They're Only in It for the Money. Or the opportunity to loot, pillage, and plunder. Bribes and financially based threats keep them in line.
Psycho Sidekick: They have a mutual friendship, or family relationship, with one of the heroes that survives despite their basically evil orientation. But don't expect them to be helpful for anybody else.
Sometimes they're just in it For the Evulz. The hero is on an exciting, heroic quest that will save the world, but it also involves a lot of killing mooks, and they've got nothing better to do right now. They want to cause chaos and rain down carnage, and this is the best way to do it.
Mayuri Kurotsuchi's moral code is non-existent if it means obtaining scientific break throughs. He turned his subordinates into human bombs without their knowledge. He conducted quincy experiments by torturing them to death. He'll even kill 28,000 people in the name of world soul-balance. His results are undeniably useful, but his methods are completely evil. Word of God stated that Mayuri is his exploration of the concept of "necessary evil".
Kenpachi Zaraki is an Ax-CrazyBlood Knight who has no problem physically assaulting his own underlings. He doesn't care whether people are friends or enemies. All he cares about is finding the strongest fighters so that he can enjoy fighting to the death. If he finds a Worthy Opponent, such as Ichigo, he'll go all out to arrange circumstances to ensure he gets the chance to fight that person, even if it means turning on his own people to achieve that goal.
Ikki from Saint Seiya is a milder version of the Aloof Big Brother and Loners Are Freaks variety. While he was purged of much of his evil in the first tournament arc, his involvement in the service of Athena is usually restricted to making sure his younger brother is safe...and killing off his attackers in brutal ways.
Xellos from Slayers, Calling him a teammate is a bit of a stretch but he does hang around the heroes and they often work together. Considering how powerful he is (one step or two steps below Big Bad depending on the season) it would be hard and dangerous to make him leave. Most of the time he's Affably Evil and dicking around with them for lolz so they tolerate him.
Case in point, Slayers Try when Xelloss actually did betray Lina in order to recruit Valgav. When Lina found out, she merely hit him on the head a few times.
Lina: Xelloss is a monster, so we expect that of him.
Diethard once again is this along the leader himself when he joins Schneizel. He's the one who justified sacrificing their official leader claiming that baits are not allowed to talk.
In Ouran High School Host Club Kyoya is a slight subversion. It is commonly accepted amongst the group that everything he does is for the sake of personal gain and profit, but Haruhi manages to prove otherwise on occasion.
Darker Than Black: November 11 plays the Best Evil Friend Variety when working with police officer Kirihara who is one of the few people he'd risk his life for and go out of his way to help. In general, Contractors are supposed to be the Token Evil Teammates of the intelligence agencies which use them for their powers and ability to kill without remorse. The main character of the series, Hei, is a slight subversion. Contractor-hating human Huang is Hei's Handler and frequently berates him for having qualms about missions and not acting as evil as a Contractor is supposed to be.
In The Prince of Tennis, Hiyoshi Wakashi is kind of the Hyoutei team's token evil teammate (his not so secret aim is to "overthrow" the captain, and he tends to be quite cynical). Also a Sixth Ranger.
Initially even more so, Akutsu Jin for the Yamabuki team (serves rocks at people, is rude to his mom, prone to violence), although it's safe to say he's revealed to be not that bad, deep down. Specially in the presence of one Takashi Kawamura or one Taichi Dan.
Barry the Chopper in Fullmetal Alchemist. While most of the cast are trying to do what's best for the country, Barry just wants to get rid of the Homunculi so he can be free to start killing again. Although his true intentions for wanting to hunt down his own body are mostly unknown.
Also later, Greed to a lesser extent.
Faye Valentine of Cowboy Bebop occasionally is this. There are times when she seems to genuinely care about the crew, while other times she's a Jerkass to everybody and seems to only care about herself. She has also stolen bounties that rightfully belonged to another crew-member at least a couple of times as well. Though, honestly, she isn't that much worse than them.
Also, she's barely a team member in the strict sense. Half the time she's on the Bebop, she's restrained while they check her belongings.
And Haruna, who displays some sadistic tendencies and is apparently determined to Take Over TheMagic World. She's not malicious, but she's extremely ambitious and manipulative, to the point that she's mostly on the good side out of convenience.
The Keroro Platoon in Keroro Gunsou has Sergeant Major Kururu, a Jerk AssMad Scientist with a fondness for tormenting his teammates, and pretty much everyone he comes in contact with. One of the earliest excuses for the frogs not making progress is that Kururu won't invent anything useful unless it strikes him as interesting at the time.
And the frogs themselves are, at least in theory, a Token Evil Team to the Hinata household, seeing as they're supposed to be taking over the world. They don't really ever make much progress, though.
Katekyo Hitman Reborn!: Mukuro Rokudo has explicitly stated that the only reason he is working with Tsuna and his group is so that he can eventually steal Tsuna's body. In a similar vein, Mukuro's counterpart from the first generation of Guardians, Daemon Spade, was stated to be a backstabber.
Despite what some fangirls will tell you and despite the fact he's almost always accompanied by an adorable bird pet, Kyoya Hibari isn't a much better person than Mukuro and Daemon. However, the first Cloud Guardian, Alaude, was said to be similar to him in his younger days but he got better (despite remaining cold and aloof), so it's possible Hibari might grow up as a decent person. As it stands, however, Kyoya isnotone.
Eyeshield 21 has Yoichi Hiruma, the scheming, trigger-happy, demon-faced captain of the Deimon Devil Bats. Agon Kongo becomes this in the World Cup arc; he only joined Team Japan because he wanted to win the three million dollars, and isn't above threatening his own teammates to do so.
There have been several Token Evil Teammates throughout the various Gantz rosters, but the two that stick out the most are Nishi and Izumi. Nishi is an extremely nihilistic jerkass whose actions are on occasion at least somewhat understandable, whereas Izumi is far more damaging.
In Flame of Recca, Recca has control over 7 dragons, all of them are more or less amiable (One of them is his Bumbling Dad), except one certain dragon named Setsuna. He hates Recca, wants nothing more than to kill him and be free, and resume his old life... as a sociopath mass-murderer. Recca still beats him down to submission.
Arlong in One Piece was this in the Sun Pirates. While there were other unsavory characters in that group, Arlong would be the first one to suggest violent terrorism towards humans. He even wanted to kill a slave just for being human.
At Sabaody, The Supernovas Eustass Kidd and Trafalgar Law briefly teamed up with Luffy. Kidd seemed to be this at the time, with his evil apparently nothing more than an Informed Ability. It wasn't. More recently, Law made a return as an ally and is a minor version this, being a much colder character than any of the Straw Hats, and acting as a foil for their playfulness. But, to his chagrin, he's found that spending too much time with them Not so Above It All opens him to their quirks.
During the Impel Down arc, we had Crocodile, who, in a textbook example of Teeth-Clenched Teamwork, doesn't get along well with Luffy at all. Or with Jimbei for that matter.
Nguyen from the Area 88 manga and OVA. Even by mercenary standards, he's an unhinged sadist.
History's Strongest Disciple Kenichi: The Shinpaku Alliance has one as the leader, Nijima. Various other characters in their orbit could also be considered as such depending on how strictly you ascribe the term "teammate" to them. These can include three members of YOMI; Tanimoto Natsu, Rachael Stanley and Kushinada Chikage. All of them have friendly dealings with Kenichi and the rest of the Shinpaku Alliance even if they have yet to renounce their ties to YOMI.
Weevil/Haga and Rex/Ryuzaki served as this in the first third of the anime's Doma arc, up until joining Doma.
Wolfwood, while not an "evil" character, actually serves as this in Trigun Maximum. Although in the anime the revelation that he was working with the Gung-Ho Guns was saved until late in its run to make it a surprise twist, the manga on the other hand revealed this almost immediately after his first appearance. Although he is helping Vash against the other GHG members, he is actually following orders to keep him alive no matter what the cost (even if it involves killing the rest of the GHG). It's only much later (after most of the other 'Guns have been killed) does he completely abandon the antagonists' side and fully start working with Vash.
InuYasha: The title character himself was this to his group at the beginning of the series, making it clear on multiple occasions that he was only helping Kagome track down the scattered shards of the Shikon Jewel so he could use them to become a full-fledged youkai. He gets better.
Card Captor Sakura: Ruby Moon is perhaps the closest to being genuinely antagonistic out of Eriol's posse; she intentionally interferes with Touya and Yukito so she could steal Touya's power for herself and let Yue, and Yukito by extension, fade and die. When she realizes the futility of her efforts, however, she backs off and limits herself to aiding Eriol.
Deconstructed later on in the story arc, in which Urza takes a team of the multiverse's most powerful planeswalkers to Phyrexia to perform a raid on the plane in his efforts to destroy Yawgmoth...including the Evil Sorceror Tevesh Szat, who had posed issues to Dominaria in the past. As it turns out, he ends up turning on his comrades and slaughtering a few of them. And Urza was fully expecting this to happen - he hired Szat just because he had hoped he would betray the team so that he'd have an excuse to siphon out the souls of Tevesh Szat and his victims and use them as bombs. Really, by this point the only thing keeping Urza anywhere close to the side of good was the fact that he was doing this in order to kill someone a hundred times worse than he was.
The X-Men like this. Sabertooth has been on the team at least twice (though one of those times it was a situation where they didn't want to kill him, but didn't trust anyone else to deal with him - he was an involuntary teammate).
Juggernaut, Magneto, Mystique... at least Juggernaut and Magneto went to genuine Heel Face Turns.
The Young Avengers has their 'Team Sociopath,' Tommy Shepard AKA Speed.
And in new series they have Token Chaotic Neutral variety with Kid Loki. Or rather, considering it's old Loki, one of the biggest bad guys in the Marvel Universe, in the body of his younger self, it's straight token evil teammate.
Also X-related, Magik from the New Mutants spent her whole time on the team battling her demonic side, but that didn't stop her from being the first to suggest killing some bad guys. When the other kids would tell her they don't kill, she would compromise by sending the villain to Hell.
An adult version of Magik from an alternate universe filled this role for a while in Exiles.
The Comedian of Watchmen, who even went as far as to try to rape one of the other members of the team. Whether or not the other members are any better than the criminals they go after is debatable (excepting both Nite Owls, whose biggest flaw in both cases is being largely ineffective), but The Comedian is definitely the worst of them and seems to thrive on torturing and killing people. He even kills a pregnant woman (carrying his own child!) back in Vietnam. He's also more or less the exact opposite of Captain America (consider his stars-and-stripes patriotic outfit), inverted on the Sliding Scale of Idealism Versus Cynicism.
And in X-Statix, there was a bizarre inversion-subversion mix with Arnie Lundberg, the Mysterious Fan Boy, as a token good teammate in a team made up of people who don't care about morality at all. Arnie is an idealistic kid who believes being a hero is its own reward, and as such is easily the most moral member of the team ever. He's also easily the one who has inspired the most fear, having terrorized his hometown with his Reality Warper powers with a total lack of remorse. Eventually friend of the team Lacuna takes it upon herself to kill him before he can cause any more harm.
Though Hsu and Chan aren't exactly the most moral duo, Gila Mobster fits this role perfectly in their misadventures, using methods which the titular brothers insist that he keep to himself and carrying out several odd jobs for local mafias and corporations which actually leads to him trying to murder Hsu in Brand Loyalty.
Loki "Trust me! I'm the God of Lies!" Laufeysson in the Danish comic Valhalla, based on Norse Mythology. Mostly saved from being hateful by being comically inept.
When the six Infinity Gems were split after The Infinity Gauntlet, they were split among five known members of Adam Warlock's Infinity Watch, with the Reality Gem given to an unknown sixth member, eventually revealed to be an extremely potent version of this trope: Thanos - not only an enemy of Adam Warlock, but the one who Adam had taken the Gauntlet from.
There tends to be at least one during in Teen Titans during any time. Rose Wilson (Revenger) and Damian Wayne (Robin) were the most recent
Karla Soften AKA Moonstone was this after the Thunderbolts turned good, having turned on Zemo out of her own self-interest and never quite making the jump to being a good person.
Doctor Doom becoming a member of the Future Foundation is the very epitome of this trope.
Green Lantern now features the New Guardians, a team comprised of one member from each of the Corps, and Arkillo of the Sinestro Corps is this trope for the team.
Blackblood of ABC Warriors was a robot literally designed to be evil, and as such has turned on his teammates on several occasions. He's quite openly said that he'd like to kill Hammerstein, the leader.
Ladytron in various incarnations of Wild CATS. An extremely powerful and volatile cyborg, she was mostly recruited onto the team because the alternative is not having her on your side. It took weeks of holographic simulations to break her down into a somewhat manageable, not-so-murderous state, but she's still only "good" in name and because her teammates force her to be.
Darkhell from Les Légendaires briefly filled this role when he agreed to become The Champion for the Guardian with his Good Twin Elysio during their crusade against Anathos; the only reason he agreed to do this was because he was given more power, brought back to life with a new body and had to kill his Arch-Enemies the Legendaries as the main mission due to them being candidates to become the hosts for Anathos' reincarnation. Ironically, he and Elysio both end up doing an Heroic Sacrifice to save the Legendaries.
In The Movement, Katharsis is this to the titular group. She is the most violent and is willing to kill or at least maim her enemies. The others have to keep her from going over the edge.
Transformers: More than Meets the Eye has a Token Evil Teammate on the crew of the Lost Light, and surprisingly, it isn't Cyclonus (who's more of an Anti-Hero in this series), it's Whirl, the mentally unstable, ex-Wrecker with a Dark and Troubled Past who is indirectly responsible for the entirety of the Great War itself (and also been voted Most Autobot Likely To Defect twice). He's had a few Pet the Dog moments here and there, and hasn't crossed the Moral Event Horizon yet, but still remains the most morally black member of the team.
Damian Wayne and Jason Todd tend to be this to the Bat-Family. How? On several occasions they have not only killed enemies, but they've also attacked and/or attempted to murder members of the Bat-Family, most notably (and frequently), Tim Drake.
Dungeon Keeper Ami has Jadeite as both a straight example, and as something of an inversion. As part of his Shades of Grey theme, he learns empathy and gains a more uplifting world outlook due to Mercury's influence. Regardless, he is by far the most straightforward, pragmatic, and blunt of Ami's advisors in regards to her goals and resorts to dubious methods at times if the situation warrents it.
Slightly Altered has Azurai, who only helps Buwaro friends find their missing family members because Buwaro's his adoptive son. While he's nowhere near as bad as his canon self, he's still done some truly horrible things like murdering Buwaro's parents, hence why the kid's adopted in the first place.
Ike of the Pokemon fanfic Pedestal first met the protagonists by attacking the narrator and ferociously declaring that he would rip them to shreds. After joining the party, he still plans to murder Namnar after a certain period of time, and after years of working with Des and Carlita, still comes very close to attacking them. Eventually, Ike morphs into a Sour Supporter.
Makuhita of the fanfic The Retelling Of Pokemon Colosseum is DEFINITLEY an example.
The Team mage in Wardens not only could care less about his fellow wardens and often sits back and lets them struggle...he actively murders other soldiers on a whim or turns them into bombs regardless of if they were dying or not. A very literal Blood Knight if you will.
Mana Ryougi is this to The Emiya Clan. She, like her mother, had a very skewed morality, but unlike her mother, she mostly works as a contract assassin, trading blood for money with few restrictions. The others have mixed feelings about her. Kiri and Aleksi have issues with her lack of loyalty to any particular cause and her willingness to interfere with them if she is paid to. On the other hand, Touma idolizes and respects her for her efficiency, iron will, and dedication to standards that she hammered into him when she trained him as an assassin. Everyone else is somewhere in between.
In That Epic Plan Beyond Birthday is this for the Kira Taskforce-at least in theory. In practice he's Light's Dragon.
In The Universiad, the Office of Special Resources is viewed as this In-Universe by some of the Forum's members or its allies who disapprove of The Unfettered extents to which they are willing to go to protect and advance the Forum.
In the fanfic The Misadventures of Cell and Frieza, the eponymous duo become this in order to defeat Majin Buu. However, this is mainly because they want to destroy the Earth and the Z-fighters themselves.
Stallionsof Harmony Verse has Sunset Shimmer being this towards Twilight Sparkle and Moondancer. When they got themselves into trouble, she was going to shift all the blame on herself, because everypony will blame her anyway. Twilight objects to that idea and reassures her that they are in this together.
Films — Animation
Mittens from Bolt is an example only in the titular dog's mind, but she sure plays the role to its hilt.
The Indiana Jones series features a lot of Evil Teammates. Even after it comes to light that Allison Doody's with the bad guys, there's still some teamwork between her and both Indy and his father. It's pretty well established that Ray Winstone's character in the fourth Indiana Jones movie, but Indy takes him along for the ride anyways.
Sorceress: I am not evil! I'm Chaotic Neutral! Everyone:(deadpan) You are evil Paladin:...and a whore.
As it happens, Paladins (in Dungeons & Dragons) have the special ability to Detect Evil and are forbidden from associating with evil people, so the paladin may have been violating his oaths by adventuring with the Sorceress.
Archer Maggott is a bigoted, psychotic, woman-hating, murdering rapist, and Major Reisman knows it. But given that Maggott is also a trained G.I., and the operation needs all the help it can get, Reisman retains his services. Maggott doesn't mind volunteering for the mission once he realizes it could save him from the hangman. Ultimately he goes completely insane, attempts to kill his teammates, and almost sabotages the entire operation, but for a while at least he was a warm body with a machine gun.
Victor Franko is a member of the Mafia (and a convicted murderer), has no respect for authority, and makes several attempts to escape and/or undermine Reisman's authority. He got better, though.
In X-Men: First Class, Erik is part of Charles' team primarily because he has a personal grudge against Shaw, and views the youngsters' mutant powers as useful tools to topple the Big Bad.
Although he's not evil, Mundungus Fletcher from Harry Potter is a criminal and a con artist. He was disliked by the other members of the Order of the Phoenix because he was considered untrustworthy. He did eventually end up stealing from a member of the Order, and unwittingly giving a horcrux over to Dolores Umbridge.
He also abandoned Mad-Eye Moody during battle, possibly causing the latter's death.
Hix was first introduced in Making Money, but as he wasn't yet on the University Council, his acceptable level of rule-breaking was much lower and he still spelled his name "Hicks".
In the Dresden Files books, the gangster Johnny Marcone is this. Although he runs a criminal empire, and has no qualms about killing most people in cold blood, he is practical, Dangerously Genre Savvy and often works with Harry, in one case saving his life. Given that he Wouldn't Hurt a Child, and keeps his word, Harry has a hard time seeing him as a monster. And we see in Ghost Story that he goes much further by funding an organization devoted to defending Chicago.
Lea. Especially in Changes. Turning everyone into hounds, ambushing fellow teammates, reminiscing fondly over past human sacrifices, all while greedily eyeing the Swords, she plays the role to perfection.
By about halfway through the series, Rachel from Animorphs was getting there. It's heavily implied that she started out with nothing but a tendency towards pragmatism and ruthlessness that was slightly more pronounced than the other team members. But the group kept needing someone to do the smart thing, instead of the right thing, and Rachel kept volunteering, and it became a part of her character. As she put it in a later book, "They needed me to be the bad guy. And I needed them to be the good guys. Because if they were good guys, and I was on their side, then that meant that I was a good guy too. Even if I was different."
Mogget the white cat/albino dwarf from Garth Nix's Old Kingdom Trilogy, actually a powerful Free Magic elemental that attempts to kill the nearest Abhorsen whenever he is freed from his binding. He frequently travels with and helps the protagonists in his bound form (though sometimes, especially during the last book, his motives and loyalties seem questionable). Still, he does come through for the good guys in the end when he lends much-needed assistance to bind Orannis, because he just loves the living world too much.
In the Druid of Shannara, Pe Ell plays this to Quickening's group, specifically inducted into the group because he was evil enough to bring about Quickening's necessary death.
By Freedom, Loki/Gragg realises that he has become this, since the Darknet community has largely evolved beyond its early disaffected-and-misfits days to encompass many normal people and has little need of sociopathic hatchetmen like himself.
Lokor in Star Trek: Klingon Empire. Of all the Klingons who consistently follow Klag's authority and have yet to pull a Face-Heel Turn, Lokor is basically the one guy who has the fewest scruples in screwing people over to get them to toe the line and not buck the system, and most of his methods are disturbing in their effectiveness. On the other hand, he's also unbelievably useful and indispensable to the point that Klag trusts him implicitly.
In the tenth Haruhi Suzumiya novel, Kimidori revives Ax-Crazy Ryoko Asakura because "Your potential usefulness was marginally greater than the threat you present."
The Reynard Cycle: Tybalt, who is a Jerk Ass at best. Reynard's continued association with him in book three is a pretty big red flag that all is not well.
In A Song of Ice and Fire, Robb Stark has one in the form of the cruel and ruthless Roose Bolton, who's more than willing to use monsters like the Brave Companions and allows his soldiers to Rape, Pillage, and Burn freely. He even goes as far as to turn against Robb purely out of opportunism at the Red Wedding, with his forces joining the massacre of his former allies and him personally killing his former king.
Andromeda: More of a "token pragmatist", Tyr was both invaluable and tried to sell out the ship/crew at least once per episode. It helps that Nietzschian pragmatism can be used to justify any action. Even Beka Valentine, a Han Solo-esque rogue, had far more loyalty and backbone. But then, Tyr was himself inspired by Avon from Blake's 7.
Connor fits this in season 4, alongside being the Tagalong Kid, due to his unstable nature.
Battlestar Galactica (Reimagined): Tom Zarek of the re-imagined show likes to portray himself as a staunch defender of the little guy, who had to resort to extreme measures to try to empower his disenfranchised people, and yet ordered things like bombing convention centers, tried to have the president assassinated when there were less than 50,000 known survivors of humanity, ran an illegal black market which had previously included the exploitation of children, and had sold his position numerous times. While he does seem genuine in at least some of his outspokenness, the fact that he could be blackmailed with this information says something about his character. And then, well... let's say season 4 gets a lot more definite on the subject of his character.
Blake's 7: As referenced in the Andromeda example above, Avon might just be the prototypical sci-fi evil teammate: snarky, argumentative, cynical, and in favor of self-preservation over doing the right thing. He repeatedly claims that he’d sell out the rest of the crew in a heartbeat if it was to his benefit. It’s not clear how much of his attitude is a bluff, but he certainly is more… morally pragmatic than Blake is. Avon is a bit of an odd example because after season two, he’s the protagonist. In fact, the only thing that stops him from leaving the Liberator is the Liberator. In the final episode of season 2, he tells Blake he's done with Blake's revolution and will only help if he is given Liberator. Blake agrees and Avon is content enough to follow Blake on what could easily be a suicide mission.
Buffy the Vampire Slayer: Spike has been nearly every level of this. He started on the road with the one time team up variety. When he got a chip put in his head to prevent him from hurting humans, he joined the Scoobies as the Token Evil Teammate, since killing demons was the only way he could get his kicks. This didn't stop him from working with Adam or being a general asshole - they only kept him around because he was occasionally useful and they didn't want to kill someone physically incapable of fighting back.
Faith believes that her Slayer powers give her the right to steal and generally run amok (eventually leading to the accidental death of a person). She soon goes from Token Evil Teammate to straight villain and The Dragon for Mayor Wilkins.
Anya's pining for her lost vengeance demon powers and lack of sympathy for humans qualified her as an Evil Teammate to begin with. Soon enough, though, she was just as goody-goody as the rest of the group, just odd.
Charmed: During his stay on the series, Cole Turner filled this role on a few occasions.
Community: From time to time Pierce Hawthorne fills this role. Chang sometimes does too. For example, when Pierce endangered Annie's anti-drug play, it was Chang who saved it.
Dans une galaxie prčs de chez vous: Being an Expy of Dr Smith, Brad Spitfire from this French-Canadian science-fiction comedy fits this trope completely: cowardly, greedy, power-hungry, Nazi-loving and all-in-all hated by every other members, the only reason hasn't been Thrown Out The Air Lock by now is because he is the only one scientist on board, and his skill are greatly needed.
Doctor Who: Snarky, cynical Turlough is like this to the affable and vulnerable Fifth Doctor after making a deal with the Black Guardian to assassinate the Doctor. He redeems himself in the endnote after half a season of plotting, but throughout his run as a companion he's just as liable to run away or betray the Doctor as he is to heroically rescue his friends, and even strangers.
The Doctor himself started out as Token Evil Teammate, and the First Doctor's character arc is about him shifting from Neutral Evil to Chaotic Good.
Farscape: Everyone is quite morally ambiguous—especially by the final season. However, in that season, Scorpius definitely qualifies. Earlier on, there's Rygel, who constantly tries to sell out and undermine the rest of the team and unashamedly jumps on any opportunity for profit. Chiana plays this part in early appearances, first (implicitly) mirdering her custodian and then torching the captain of the Gammak base to a crisp.
Firefly: Jayne is very much this for the main characters. He always points out when they're about to do something more honorable than profitable and was a prime example of Recruiting the Criminal... well, enemy criminal. He's Only in It for the Money, and is probably the staunchest proponent for getting rid of the Tams, though the one time he tried to do so in Ariel, he got betrayed by the guy he worked with and almost got Thrown Out the Airlock for it by a furious Mal. Also, in Serenity, after River gets triggered and Mal still keeps her on the ship, Jayne tries to kill her in order to get the Alliance off their backs. However, Jayne definitely shows that he has good in him. Whether it be his shame of betraying Simon and River after Mal was about to throw him out of the airlock (it wasn't just fear but legitimate shame), or him eventually advocating in favor of doing the right thing near the end of Serenity.
Glee: Santana has increasingly become this in the second season. Quinn can flip in and out of this role.
Gossip Girl: Chuck Bass is the Token Evil Teammate of the Non-Judging Breakfast Club. True he's mellowed, but a guy who's attempted to rape another team member definitely counts as evil.
House: Oddly enough, this show features its main character Dr. Gregory House as one of these. Whatever his actual moral alignment may be, he's a brilliant diagnostician, but his demeanor is that of a snarky jerkass with an addiction to painkillers, and he's made it quite clear that solving complicated medical mysteries is pretty much just a fun game for him. Failing to save a patient's life is usually more of a blow to his ego than a source of sorrow.
How I Met Your Mother: Has Barney Stinson, the embodiment of this trope. A Ladykiller in LoveThe Casanova to the extreme who works for Mega Corp., which is implied to have all sorts of really evil things going on with North Korea and even somehow contaminating the drinking water in Lisbon for some reason? Yeah, pretty evil. The other characters occasionally wonder why they even hang out with Barney when he's being exceptionally assholish. The reason, of course, is that he's like family to them, and no matter how horrible he acts, they can't bear to abandon him, as Ted realized in season 3, and Marshall in season 6.
Human Target: Guerrero. He is intensely loyal to Chance, but that seems to be about it as far as morals go. Threats, torture, murder? Check, check and check. He doesn't look like much, but his name is enough to cause an experienced thief to wet her panties.
iCarly: Sam. If the plot requires anything that isn't lawful, Sam will suggest it and carry it out.
Legend of the Seeker: Cara might qualify as this after her Heel-Face Turn. Although she's extremely loyal to Richard and eventually admits, albeit begrudgingly, that she cares a lot about her teammates, she seems to really enjoy killing and torture, and finds the other characters' displays of love and affection nauseating.
LOST: Ben fits this trope in the sixth season. He's still a manipulative sociopath, but this time he's on the losties side. Also, Sawyer pretty much filled this role in the first season, or at least he was the token Jerk Ass.
Lost in Space: Dr. Smith. While not outright evil, he's propelled largely by self-interest and tends to have such poor judgmentit can become a real liability. The aborted movie franchise did make Smith substantially more malevolent and intelligent. However, this is really a case of Villain Decay. Early episodes showed him to be much more malevolent and the show itself was much more serious. It quickly devolved into slapstick. Also, in the earlier episodes Smith's unquestionably necessary skills as a doctor prevented the Robinsons from simply flushing him out the airlock, whereas in the later episodes he contributes nothing to the team and all he ever does is get in the way with his self-serving schemes.
Luther: Has Alice Morgan, at least after the finale of the first series. Even though Luther's a policeman and she's an unrepentant murderer and sociopath, the two have an understanding and friendship of sorts and are perfectly willing to help each other with their various problems.
M*A*S*H: Major Charles Winchester. He's not above trying to get something out of his forced residence at the 4077th (especially if it's at the expense of his tent mates), but he does do his best to take care of the patients. Turns into a Jerk with a Heart of Gold later in the series. Also, Major Frank Burns (for whom Winchester was the Suspiciously Similar Substitute) is a better fit for this trope, given that he actually tried to get Hawkeye killed at least once (a depth to which Charles would never stoop).
Misfits: Nathan isn't quite evil, but he's a bullying, self-obsessed, borderline-sociopathicTed Baxter of epic proportions, who is regularly suggested to have some kind of undiagnosed mental illness.
Person of Interest: Shaw as of season 3. She tends to argue the merits of just killing the perps rather than going to the trouble of aiming for non-lethal takedowns and prefers spending time with Bear to the rest of the team. Root also becomes this somewhat as she is working as an agent of The Machine and will do almost anything it tells her.
Revolution: While not evil per se, Miles certainly is a Jerkass and an Anti-Hero. Major Tom Neville is a straight example as of episode 16. The good news is that he wants to take down Monroe. The bad news is that as his son stated, he doesn't care whose side he's on, as long as people kiss his butt. Episode 19 and the first season finale has Tom Neville successfully take over the Monroe militia, while his son Jason doesn't have a clue as to what he should do about this.
The Sarah Connor Chronicles: Reprogrammed Terminators like Cameron, Weaver and those employed by the Resistance fit this category to a T. Cold, logical, unstoppable and brutally pragmatic (Cameron would kill anyone she even suspects of being a threat, and Weaver slaughtered an entire warehouse of people for working for Skynet when John Henry intercepts an unsecure communication) — be glad they're on our side. Of course, "Sometimes they go bad. No-one knows why."
The Secret Circle: Faye from is a Subverted Trope: she has all the surface traits, but doesn't want to hurt anyone and is scared of losing control of her powers. Jake, on the other hand....
Stargate Atlantis: Todd the Wraith occasionally allies with Atlantis versus Replicators, Genii, other Wraith clans, etc.
Stargate Universe: Dr. Rush is the only person smart enough to help out his crew mates most of the time. Which he stranded them on in the first place. He also is arrogant, doesn't particularly care about what happens to anyone else on the ship and is insanely dedicated to carrying out Destiny's mission.
Star Trek: Deep Space Nine: Gul Dukat works with the crew of Deep Space Nine and forms a mutual trust with Sisko to eliminate a greater evil far more often than Sisko should trust him. At some point in the series, the two become mortal enemies.
Garak also qualifies, given his penchant for lying, previous job as a spy/torturer, and "ends justify the means" attitude. He had no qualms about committing extortion, blackmail, and murder to convince the Romulans to join the Dominion War, and when someone doesn't believe he'd shoot a man in the back, his reply is simply, "It's the safest way, isn't it?" Despite all this, he's almost always on the side of our heroes.
Supernatural: Dances around this a lot. Season 3 gave us Bela, who while pretty evil wasn't exactly a team player, and Ruby, who turned out to actually be The Mole. Finally, however, season 5 gave us Crowley, who, while still perfectly willing to kill innocent people and send souls to hell, proved to be a valuable member of Team Free Will.
Survivors: Tom Price in the 2008 remake of this BBC drama, only his position as the Big Guy of The Family has kept the other survivors from killing or permanently banishing him, and even then, only barely.
V (2009): Hobbes is a mercenary wanted by the FBI who is forced to join the Fifth Column after the Visitors frame him for a crime he didn't commit... which is not to say that he hasn't also committed other crimes which were just as bad or worse.
In the V: the Final Battle mini-series from the 80's, Michael Ironside portrays merc Ham Tyler, whose was initially distrusted by the Resistance as being a warmonger.
The Vampire Diaries: Damon, in the beginning. He's not even LIKED by most of the team, and the main reasons they keep him around are that he's Stefan's brother, it means they know where he is and he'll lend a hand if it serves his purposes. In Season One, they just had to deal with having him around because he was too strong to fight. In Season Two he's more of a team player, but maybe that's because Bonnie has proven that she could (and almost DID) kill him if angry enough with him. Also, Elijah joins them in Season 2 despite being rather antagonistic earlier in the season.
Warehouse 13: H.G. Wells goes from pure villain to a member of the team. Artie is certain she'll betray them at any moment. And as it stands he was right. She eventually betrays the group to wield one of the most powerful and destructive artifacts there is that nearly causes a mass earthquake capable of wiping out all life on earth after (in her eyes) seeing the future world decay so horribly over the years from her time.
White Collar: Similar to House, the main character (or one of them) is more or less this: Neal Caffrey is a Boxed Crook working with the FBI in exchange for not being in prison. Subverted inasmuch as Neal shows signs of reform—to say nothing of the fact that, as a good-natured forger and con artist, Caffrey wasn't terribly evil to start with. He is also extremely unwilling to use violence, which is a major factor in what makes him redeemable.
Young Dracula: Ingrid is this whenever she helps Vlad, which isn't often.
In Noob Gaea is not exactly this for most of the series as despite her Manipulative Bastard status, as two of her guildmates could get quite selfish when it came down to it. They were also all equally guilty of considering that the The Millstone of the the team was the sole reason of their lack of progress despite their respective flaws playing a big part in it also. She however definitely became the token evil of the team after the two other morally ambiguous members of the team left the guild and all the other remaining members were much more on the good side.
Myths & Religion
In The Bible, Joab son of Zeruiah acts this way for David, ostensibly commander of David's army but doing evil things like disobeying David to kill David's son Absalom (who'd just staged a failed coup) and his intended replacement Amasa. Unlike many examples of the type, he does get killed for it once he outlives his usefulness (and supports a rival of the legitimate heir to the throne).
In some interpretations, Judas followed Jesus more out of personal ambition than true belief, and he sold Jesus out when things weren't quite going like he expected.
Loki seems to fill this role for the Norse Gods sometimes. Not that the rest of them are really paragons of virtue.
In a lot of cases they were asking for it, really.
CHIKARA King of Trios 2010, Night I, April 23, 2010 was supposed to have featured a match between Team Mexico (Skayde/Turbo/El Valiente) and the BDK team of Claudio Castagnoli, Ares and Tursas. Team Mexico didn't appear due to El Valiente getting double booked and wrestling on the CMLL show instead. Skayde apparently tried to hold up CHIKARA for more money, leading to the company cutting all ties with him. Names were drawn out of a hat for a replacement team. The first names were Well Dunn, but, sadly, Steve Dunn had passed away a year earlier. Then they drew StrikeForce, who were not there. Then they drew CHIKARA regulars the Osirian Portal (Amasis and Ophidian), who, of course, were there and came out to the cheers of the crowd. Then Sara Del Rey's name was drawn, meaning the Portal was teamed with a BDK member against three BDK members. During the match, Sara broke up the Ophidian Death Grip on Claudio by kicking Ophidian low. She couldn't be DQ'd because it was her own partner. The BDK won, of course, with Ophidian taking the Ragnarok for the pin.
A Token Evil Teammate is a common occurrence in any group of players, regardless of system or original intent of the campaign. This is frequently a cause of friction inside the group, and certainly the cause of much interesting character development and actual role-playing. Why is the lawful good paladin working with Nazis? Let's find out!
Among the sample characters given in GURPS 4th Edition, Baron Janos Telkozep seems to be one. He's a vampire who's backstory is that he's working for the good guys for purely selfish reasons, and close inspection of his character sheet suggests he's not a Friendly Neighborhood Vampire but rather a murderous, greedy bastard. Oh, and he's named after a god with two faces.
The Space Marines of Warhammer 40,000 have two worthy nominations: the murderously psychotic Flesh Tearers and the hyper-arrogant and haughty Marines Malevolent. They're loyal to the Imperium of Man, but several of their actions are so brutal and immoral that you wonder sometimes why they haven't been declared Excommunicate Traitoris by the Inquisition.
Speak of the devil. The Inquisition fill in this role for the Imperium as a faction. No-one in the Imperium is squeaky-clean apart from maybe some of the more rational and casualty-conscious Imperial Guard and PDF regiments, but if you have an Imperium character who opposes the protagonists or becomes too extremeeven for them, chances are very, very, very high that it will be an Inquisitor.
Of the Icons of 13th Age, the Crusader is the only major genuinely evil NPC to be considered a full part of the sort of heroic Dragon Empire, because even though he's listed as "the fist of the Dark Gods" in multiple places, he's at least kind of loyal to the Emperor and spends most of his time fighting demons rather than anyone else. To a lesser extent, the Three may qualify, because while they're malevolent chromatic dragons, they're still technically part of the Empire due to a past scheme of the Blue. Of the other evil Icons, the Lich King, the Diabolist, and the Orc Lord are much closer to being part of the problem than the solution.
Kreia in KotOR 2 if the player character is light-sided, as she believes in balance above all else, and so gives "evil" advice when players do good things.
There are others who start out evil, and can be redeemed, in KOTOR II - G0-T0 comes to mind.
Star Wars: The Old Republic: The Jedi Knight has Lord Scourge as one of their companions, he is a Sith Lord who is happens to be the Sith Emperor's personal body guard. He sides with the Jedi because he saw that they would be the one who will defeat the emperor. It should be noted that in the past he aided Revan and the Exile in taking down the Emperor, but betrayed them when he had a vision that they would fail, and the Jedi Knight would be the one who will kill the Emperor.
One-of-Many, an undead Hive Mind, could possibly be this in the expansion Mask of the Betrayer, but this would largely be averted (provided the player doesn't choose to make a sudden Heel-Face Turn) by the fact that the PC would have to make a consciously evil choice to get him/it/them/? instead of Okku (the corresponding good character).
Leaving aside the fact that Storm of Zehir lets you hand-craft your own party, T.E.T. and all if you so desire, among the cohorts are the deep gnome wizard Chir Darkflame (Chaotic Evil), the aasimar Shadow Thief Belueth the Calm (Neutral Evil), and the half-drow warlock Quarrel (Chaotic Evil).
Nix is more of an Anti-Villain. While she is willing to kill it is more due to her traumatic experience and wanting to get revenge. After the plot twist, she is willing to sacrifice her life to stop the Beast who will destroy everything, compared to her counterpart Lucy, who joins with the Beast to save herself.
Not really noble goals fighting the Beast. When you fight her in the Evil ending she basically says that she's only fighting the Beast because of desire for vengeance and because she doesn't want to be part of a crowd of Conduits.
The Silencer, of the Crusader series. An unusual example, given that he is the player character.
Warlocks and Death Knights seem to serve this role in World of Warcraft. Warlocks fit the role very loosely, since they indeed horribly kill their enemies and steal their souls, but their class quest chain is dedicated to resisting the Burning Legion's influence and not succumbing to evil.
As well as many Forsaken characters, who are not saints.
And Death Knights feed by the very act of killing, which is perfectly suited to the role of adventurer..and thus not really fitting the trope very well. All of what made the DK class "evil" was because they were compelled to do Arthas' will, which disappears after the Knights of the Ebon Blade rebel.
On the other hand, many of the Knights of the Ebon Blade take questionable approaches to fighting the Scourge, from being willing to fire even while risking hitting web-wrapped "human shields" to destroying the soul of an enemy commander.
In Wrath of the Lich King, Malygos, leader of the Blue Dragonflight, has gone insane and is leading his dragonflight in an attempt to destroy the world due to what he sees as overuse and misuse of magic by mortals. The Wyrmrest Accord is an alliance of the other four dragonflights of Azeroth against the blues. The black dragonflight is part of the alliance. The leader of the black dragonflight also wants to destroy the world, in his case because he was corrupted by Eldritch Abominations, and in fact he would try to in the very next expansion, but he wasn't around during the events of Wrath of the Lich King. So the blacks, while evil in general, weren't making a concerted effort to blow things up when the blues were.
Korgan Bloodaxe in Baldur's Gate 2. His Chaotic Evilness is to the point where some people LEAVE YOUR PARTY if the right dialogue goes down. He is also immensely badass — just look at his name.
To be specific, Korgan will chase Aerie out of the party by verbally abusing her. If you're playing the expansion, however, Aerie instead starts verbally insulting him right back — at which point Korgan reveals it was a Secret Test of Character to see if she was able to stand up for herself or not — and now that she's proven that she does, he no longer has a problem with her.
The Baldur's Gate series is pretty rich in villainous PCs. In Throne of Bhaal, this extends all the way up to bringing the villain of the first game Back from the Dead as a recruitable party member!
We also have Edwin, snarky Gender Bender wizard who talks to himself frequently about fireballing the party as they sleep. He also hated Dynaheir, Minsc's partner in BG1; in BG2 she's dead, and he mocks Minsc about it, showing zero sympathy. He seems to be driven by ambition and thinks the PC is a quick route to power - and despite mutinous mutterings, Edwin is one of the most loyal NPCs in the game, and it is perfectly possible to go through the game with a Good party, high Reputation, good deeds left and right, and all Edwin will do is some amusing snarking about it.
Myron from Fallout 2, who's evil extends to potentially drugging and raping a female PC with a very low intelligence score. He is intended, to all appearances, to be a character that nobody will like (being annoying, beyond the Moral Event Horizon, AND bad in combat), and which everyone will only use for his abilities. He's easy to keep in line just with threats, since he's so pathetically weak in every way. Even if you let him live, he gets murdered in some back alley in the epilogue, regardless of your actions. Even the writers couldn't stand him.
Jericho from Fallout 3 was formerly part of the Raiders, who are notorious murderers, rapists, sadists and possibly cannibals. Though he nominally works as a part-time protector for the settlement of Megaton, he usually ends up getting drunk off his ass and reputedly attempted to rape one of the local residents. A player with bad karma (and 1000 caps) can convince him to come out of retirement and become a companion.
The Omertas are this for the Three Families on the Strip. The Chairmen and the White Glove Society have their good and bad members, but every Omerta you meet is a vile bastard.
Orion Moreno of the Enclave Remnants. The others were basically good people who joined the Enclave to bring order to the Wasteland and regularly subverted their more vile orders (and one of them outright quit the organization even before its defeat by the NCR), but Moreno is a bloodthirsty true believer in the Enclave's fascist ideology who's not a bit sorry for the innocent people he killed.
Joshua Graham was originally supposed to be one of these in Fallout: Van Buren, where he was known as The Hanged Man. However, due to the fact that J.E. Sawyer decided that this did not make for an interesting character, Graham appears in New Vegas as a deeply conflicted yet incredibly brutal Atoner. Also, Ulysses was originally meant to be a Legion-affiliated companion (and in the game was a former Legion spy/scout) but was cut from the game proper, though he becomes the central figure of the Lonesome Road DLC.
In DLC Dead Money, Dean Domino plays this role, being practically responsible for everything that went wrong with the Sierra Madre due to being jealous of the creator. If the player gets on his bad side, he will try to kill you off near the end.
Colonel Cassandra Moore is this to the NCR. While most of the NCR higher ups are Reasonable Authority Figures (Hsu, Crocker) or at the very least flawed antiheroes (Hanlon, Oliver, Kimball), Moore is an outright sociopath and sadist who gleefully advocates mass murder, constantly insults and belittles the Courier (especially if they solve her missions peacefully), fires Ambassador Crocker in a blatant overstepping of her authority simply because he helped solved the crisis with the Kings peacefully instead of committing genocide on them, and in general comes across as a psychotic, bloodthirsty warmonger. Even Josh Sawyer considers her scum, changing her karma from Neutral to Evil in his unofficial patch.
Ceville from the game Ceville is one. He, in fact, is the disposed former tyrant of the kingdom - your first act while playing as him is sending the Three Little Pigs and the Big Bad Wolf into slave labor and stealing all their possessions. He never really changes his personality or attitude during the entire game. The only real reason he tolerates Lilly is because she's useful in his quest to get revenge and (sorta) take back his kingdom. Despite being a stereotypical evil tyrant though, Ceville shows quite the amount of intelligence and foresight; he's well aware that he can't just kill, say, his favourite cook if he wants food later and dwarven exploitation of the elves and the forests is bad (if only because they're greedier than he). Of course, once he comes to see how greedy and evil the senators can be, he starts to get appreciative of the new 'democracy' in his former kingdom. Paraphrasing his words, they're just as bad and decadent as he was, they just can hide it better.
Reaver in Fable II: he's arguably more evil than the game's main villain, being not just a mass murderer but cold-blooded and sociopathic. The only thing that keeps him from being a far greater threat to the world is his lack of ambition and scope.
Fire Emblem: Path of Radiance/Radiant Dawn has a few. First is Izuka, the Mad Scientist from Po R who ends up with Daein again in RD, who utilizes deplorable tactics for the cause, though he was serving two other causes at the time, all three of which sought very different ends. Second is Soren, who really seems indifferent to everything other than Ike, and is more suspicious of others' motives than his teammates. Finally Shinon, an unabashed racist who never repents even given the somewhat Anvilicious race-based events in the game.
Morrigan in Dragon Age: Origins is the daughter of the infamous Witch of the Wilds, Flemeth, and while she claims to be an ultra-pragmatic survivalist, most of her actions show her to be rather cruel, disapproving of virtually anything you do that isn't sadistic and cruel. Oh, and you later learn that the only reason she joined you was so she could birth a child with the soul of an Old God. Of course, she does have standards... just not many.
There's also Zevran, an assassin who initially opposes the party, but can eventually be convinced to join you. Even if he does, he never quite drops his "evil assassin" nature. Unless the PC - who can be of either gender - romances him and convinces him to turn against his old assassin's guild in the endgame, in which he becomes a bit Heroic Neutral.
Dragon Age II is set in a Crapsack World with Gray and Grey Morality, but a couple stand out. Isabela, a pirate who stole the qunari's most sacred relic and is willing to let the qunari go to war with Kirkwall to save her own skin (unless you convince her to pull a Changed My Mind, Kid). Anders is a Well-Intentioned Extremist mage possessed by a spirit of Justice whose inability to deal with human emotions is steadily turning it into Vengeance. At the end of the game, he commits a terrorist attack to spark mage revolution - you can kill him, tell him to go or let him rejoin you. Of course, the rest of your teammates have their own flaws (particularly Sebastian, who vows to recruit an army and raze Kirkwall to the ground if you spare Anders after the Chantry attack). This is perhaps the biggest Dysfunction Junction in Bioware history.
Played with in Merrill's case, as despite being a Blood Mage who sought out a Demon to help her rebuild an Eluvian, Merrill frequently comes across as one of the kindest, most friendly members of the entire party;
Hawke: Merrill couldn't hurt you if she tried. At worst, she might make frowny faces.
Mass Effect 2 gives you the psychotic former lab rat Jack, the revenge-obsessed mercenary Zaeed, and the asari sex demon Morinth (who you can only recruit if your Shepard agrees to kill another teammate instead). The Mass Effect 2 squad is quite far from the "heroic" side of the scale, when you consider that Thane Krios, an assassin, is one of the most moral characters in Shepard's team.
Jack and Zaeed, while they don't end up being fully redeemed, can at least be convinced to see things in a Paragon fashion, Jack by helping her deal with her past and convincing her that you're not merely out to just use her and Zaeed by punching him in the face and threatening, at gunpoint, to let him burn in a factory like he would have done to innocent hostages. Morinth, on the other hand, is a monstrous character who has no intention of ever changing and enjoys what she does.
Mass Effect 3 has Javik, though he's not so much evil as he is just brutally pragmatic and ruthless in dealing with the Reapers. He also has zero tolerance for synthetic lifeforms and believes that they have no right to exist.
Then there's Aria T'Loak. Sidequests she give you during the main course of the game implying assassination of head of one crime group to promote Aria's marionette or turian general, who stops the other groups from plundering the weapon deliveries (which can be avoided), or releasing the Ax-Crazy head of the third group from C-Sec (which can be avoided as well, by provoking her vice to kill her to take her place). Then she becomes an actual teammate for the Omega DLC, where she ruthlessly forces Shepard to kill hundreds of Omega civillians just for her to survive (which she does anyway), and then murders the surrendered Cerberus general, if not stopped.
In a sense the Batarian Hegemony is this to the other Citadel races. They're the only member nation with a garden-variety dictatorship for a government and which still practices slavery. They're considered a rogue state, but not to the extent of the Terminus Systems which are just a loose conglomeration of feuding fiefdoms.
Suikoden V has Nakula, an Ax-Crazy killer who makes absolutely no attempt to hide the fact that he wants to murder one of your other teammates.
A little elaboration is needed. He's not "evil by design". Rather, he's just insanely pissed one of your other teammates murdered his father, and though he really wants said teammate to die (who even acknowledges he's right to be so angry), he's willing to be professional enough to put his grudge aside to aid you, even against his own people, mostly because they gave him up for dead.
Green Goblin and Venom eventually join your group in Marvel Ultimate Alliance 2 after you free them from being controlled by the Fold, a hive mind of nanite-possessed people. Judging from their dialogue with other characters, where they're total Jerkasses, they're not too happy about it. The partnership between them and the heroes is a strict Enemy Mine to take down their common foe.
A lot of the hirable mercs in the Jagged Alliance games are either Axe Crazy, massive Jerkasses, or both. They'll ignore orders if they're busy trying to kill a baddy, annoy other team members so much that they quit, or (in some instances) murder teammates that they dislike between missions.
As of the true ending for BlazBlue: Continuum Shift, the main group of heroes have two of these in the cases of Jin and Kokonoe. Though to be fair, they're not so much evil as "total prick" and "amoral Mad Scientist", respectively. However, this might be subverted that Jin is put under tutelage of Jubei, one of the few unflappably good persons in the universe, meaning it's just a matter of time until he stops being a Token Evil Teammate. Kokonoe on the other hand is standing on the edge of the Moral Event Horizon and seems undeterred by that fact, too, so the only thing "good" about her right now is that she fights Terumi.
Speaking of Terumi, he was the Token Evil Teammate of the Six Heroes. He only allied with them out of nececity when he realized that the Monster of Mass Destruction that he had secretly created wasn't controlable, and since it was now indiscriminately destroying the world, as opposed to destroying it the way Terumi wanted it to be destroyed, it simply HAD to be put down. Also, one of the heroes, a witch named Nine, put him under a geas that he WILL have to obey her so he's steered to destroy his creation. When the monster finally had been killed, Nine managed to catch whiff of the fact that it had been Terumi who set it loose in the first place, so he simply HAD to kill her (that and he didn't take being mind-controlled that well)... Guess who of the two people mentioned in the above paragraph Nine was the mother of? I'll give you a hint: It wasn't Jin.
Now that Blaz Blue Chrono Phantasma is announced, it has been revealed that there's ANOTHER Token Evil Teammate amongst the Sector Seven... Azrael. At least Kokonoe can be touted as a Nominal Hero. Azrael is already said to be a villain of the series, though he may be unrelated to whatever the main villains are planning.
Okage has one (kind of) in the form of Stan. Evil King Stan believes himself, clearly, to be evil, and thus goes along with Ari to destroy the other Evil Kings and regain his power to do...evil things, apparently. Ironically, a majority of the Evil Kings Ari defeats ends up joining their group.
In Fist of the North Star: Ken's Rage, Jagi becomes this for the Hokuto side in Dream Mode, choosing to take his chances with his brothers after royally pissing off Thouzer. Jagi was one of the biggest monsters in the series, although for this one mode, his brutality has been toned down with some hilarious moments.
This also extends to Raoh of the Hokuto Side, since by default, he's the ruthless Big Bad, and even when he's a Noble Demon, he's still got the evil within him.
In Namco × Capcom, amongst the multitudes of good heroes, one of the members you can get is Tekken's Heihachi Mishima, one of the chief antagonists of the series. Though to be fair, he's on the 'Thou' part on the Eviler than Thou deal against Devil Kazuya...
In the original translation of Final Fantasy Tactics, Gustav Margueriff seems to be this for the Death Corps. Aside from his Marquis-kidnapping shenanigans, which damaged the reputation of the Corps (just as the guy who was paying him off to do it intended), his Brave Story biography had it that he was kicked out of a knightly order for his war crimes (i.e. rape and pillaging) before joining up with The Idealist Wiegraf's forces. The new translation, however, completely inverts his background—the rest of the order was full of war criminals and Gustav left in disgust, though this doesn't stop him from making life difficult in the present.
Iori Yagami plays this for his official teams in KOF 2001 and XI.
In Magical Girl Lyrical Nanoha A's Portable: The Gears of Destiny, everyone who had joined forces to fight the Unbreakable Darkness is doing it for good reasons, may it be to stop the Eldritch Abomination from destroying everything, to fix the mistake they did for unsealing her in the first place, or because they're completely loyal to both their master and their newfound friends and would like to have fun times after beating the threat. Well, everyone that is, except for Lord Dearche, the Evil Overlord-like Humanoid Abomination who's only doing it because she plans to take the unlimited power of the Unbreakable Darkness and use it to kill all her non-Material allies so that no one would stand in her way as she begins a reign of darkness! She was slightly annoyed when her fellow Materials protested her plans since that would mean that she'd kill their new friends too. Damn minions straying from their original mission of bringing chaos to everything and becoming all nice behind her back...
Margrid The Sly joins your party in Guild Wars. She's a member of the Corsairs, a ragtag group of bandits you've been fighting since level 1. It just so happens she can provide you with a quick escape from one mission, and she has no qualms with helping you as long as you can pay up. She ends up joining you permanently, though (she claims) it's more for money and treasure than the chance to be a hero.
Also, Magik in the same game, if you get her, in a weird way. When she join you, she could count as a normal heroine. However, as of Avengers vs. X-Men, Magik turned out to be Evil All Along, so she could've counted. However, for the game, her 'evilness' have been toned down a bit, subverting this trope.
In Rosenkreuzstilette Freudenstachel, Eifer Skute was an interesting double subversion. While the Schwarzkreuz was already an antagonizing group to begin with, Eifer showed that she was even EVILER than the rest of the bunch when she not only betrayed Pamela, but also revealed that she murdered the pope, and that her true allegiance goes to none other than Iris.
That doesn't stop her from being Easily Forgiven in Pamela's side story, however.
Malva is this to the Elite Four in Pokémon X and Y - she was once a member of Team Flare and constantly talks about how much she despises the player for defeating them. The other Elite Four members don't seem to mind this.
Similarly, the fact that Giovanni was the leader of Team Rocket did not prevent him from being the Viridian City Gym Leader in Pokémon Red and Blue, or being brought back in the Pokemon World Tournament in Generation V even after ownership of the gym was relinquished to Blue.
Danganronpa's Byakuya Togami dances the line between this and Anti-Hero; the snooty heir of the powerful Togami family, who quickly and ruthlessly takes to the game, openly telling the others that they mean nothing to him. While he does do a huge amount of detective work during the various investigations, he'll also refuse to divulge information and at one point even plants false evidence to throw off the investigation and make things more interesting. But then eventually even eviler Token Evil Teammate is revealed in the form of Fukawa's other personality, the Serial Killer Genocider Syo.
Not to mention Junko Enoshima, aka Mukuro Ikusaba, one half of Super High School Level Despair.
In League of Legends, the faction of Ionia is filled with heroic characters who would usually oppose the evil factions like Zaun and Noxus. That is, until the introduction of the Dark Sovereign Syndra, a woman with immense magical power, cares nothing except exercising her power and HATES being restricted for 'self control', so in malice, she killed her own master who suggests her that and then decides that Ionia's current leadership is too much of a wuss for her tastes and is plotting its destruction.
Another evil Ionian is later introduced in form of Zed, the Master of Shadows, the only evil Ninja in the game. After driving out the old order of ninja who are more heroic (Shen, Akali and Kennen), Zed made it his mission to convert everyone to his dark arts of ninja and kill anyone else who are weak or opposing him. Naturally, both Zed and Syndra only have each other as allies as listed by Riot.
Arudin from Dungeon Crawl Inc. is this, though he insists he's "colorfully pragmatic." His most vile deeds occured years before he joined The Team, when he was an agent of the elven terrorist organization Eldreth Veluuthra. He did a Heel-Face Turn and nowadays he's mainly a snarkyJerkass.
Honestly, Thief and Red Mage are bad enough that classifying Fighter as the Token Good Teammate would probably be more accurate.
While the Light Warriors as a whole are inept, stupid, violent, destructive and selfish, Black Mage stands out because he wants to destroy the world and everyone in it for no real reason. It's suggested that its his own presence that causes the rest of the Light Warriors to be what they are.
Richard in Looking for Group (pictured above) is this. On page two, we see him use an innocent bystander as a human shield. He then gleefully considers the prospect of killing the man's wife and young son, to "complete the set." The rest of the party is grey or good (Cale).
Oddly enough, despite Richard killing Cale the first time they met (he got better), and Richard's constant Crossing the Line Twice, by now Cale misses him so much when he is not around that he set his own hands on fire reminiscing. When Richard returned, there were hugs.
Also interesting in that it's played completely straight, bordering on deconstruction. The implications of a mostly good party putting up with the sometimes utterly despicable actions of a teammate who shows them little loyalty are thoroughly explored.
And then Reconstructed with Roy giving a lecture not only on how Belkar can be controlled, but why it would be a bigger risk not to try.
Nevertheless, Belkar still is very much "south of Neutral", in Haley's words - which is sometimes not a bug, but a feature.
Later on in the story, he loses his status as the only evil character after Durkon becomes a vampire, and has an alignment shift into Lawful Evil, though after rejoining the Order he's still mostly the same character.
Bun-Bun is a sociopath through and through, but the other characters keep him around partly out of sympathy, partly because his raw toughness comes in handy, and partly because he'd kick their asses for trying to get rid of him. Over the years, the cast has gotten quite good at "Bun-Bun-fu", arranging situations so that it's in Bun-Bun's best interest to help them.
Riff: I'm going to sweeten the deal! What do you think of this, Bun-Bun? Bun-Bun:(unimpressed) It's an empty wallet. Riff:(points to bad guy) And I bet his is full of cash and credit cards. And you've got to bodily throw one of us out. Bun-Bun: Fair enough! Time to mug and take out the trash!
Even more blatant during the ROKEN arc, where Bun-Bun goes up against Oasis under the guise of doing it only for a huge pile of cash, only when he finally encounters her he has this exchange:
Bun-Bun: I'll get right to the point, Red. You simply have to stop messing with and killing the dweebs in my life. They suck, I know, but they're my dweebs. You're making me mad. But you know what's going to make you madder than me? I know where Torg is and I'm not telling. So what are you going to do about it, Crazy-Pants?
Each time he got drunk he would tell the rest of the cast that he actually appreciates them...
Girl Genius: Baron Wulfenbach seems to keep Bangladesh Dupree on the payroll because it's better to have her using her destructiveness at his call rather than simply running loose. Of course, that leash isn't very tight.
Luke from Freakangels decided one day human morals really weren't his thing and has been going downhill ever since.
Bezzler the thief in Nodwick essentially stole everything he could get his hands on and nearly bankrupted his party several times before Yeager slipped him a "Magic Helm of C'ntrol-Ault-Delete" (and again until Nodwick dealt with him after this wore off). Although in day-to-day life Yeager seems to play this role despite not being officially evil (often helped by Artax), largely due to his tendency to treat henchmen as Acceptable Targets.
Ken in No Need for Bushido is a Sociopathic Herojerkass who is something like a combination of Mugen and Prince Zuko but without either of their noble qualities. He's shown brutally mugging innocent people several times as a way to keep the group in-funds, and his good teammates are willing to tolerate this.
Bob in Bob and George is evil, but still hangs out with his brother George and the rest of the main cast. He even saves George from trouble a few times. However, none of this stops him from occasionally trying to take over the world or kill everyone.
At first, the Trolls in Homestuck seem to have one in Terezi "gallowsCalibrator" Pyrope. In Act Five, however, we meet the other Trolls; compared to Vriska "arachnidsGrip" Serket, Terezi is a saint. The worst thing Terezi has done was leading the protagonist to get himself killed by taking on enemies stronger than he could manage in an alternate timeline, and she did this knowing he would be back. Vriska, on the other hand, forced one of her teammates to jump off a cliff and paralyze himself, then mind controlled another teammate into murdering his lover, and forced Terezi into staring into the sun until she went blind. Terezi haskilled trolls during her time as Vriska's partner in FLARP, but according to her, she only killed the "bad" ones, while Vriska just killed everyone.
When he's sober. When he's drunk, he turns into a nice guy.
Galatea in The Inexplicable Adventures of Bob! seems to be very slowly growing a set of morals, thanks to her family's influence. She at least acknowledges that hurting innocent people is bad, but she still believes conquering a planet and setting yourself up as dictator is okay as long as no one gets (immediately) hurt. Bob pointed out that people would inevitably get hurt in the long run, and that gave her pause. So, she's gettin' there...
Trudy of General Protection Fault, who was quite over-the-top evil in the first few years, literally as well as figuratively kicking dogs. As Cerebus Syndrome set in, she became a slightly toned down villain who was manipulating the rest of the cast to take over the world. After being defeated and forced on the run, her ex-boyfriend Trent took over her position, proving to be the most selfish and amoral of the GPF crew during his time there. The fact that both of them were in the same position gets lampshaded.
Nick: Do they make marketing people in a less maniacal flavor?
The trope isn't played completely straight with Trent, however. Dwayne shows more patience with his antics than he really deserves, though it's fair to say his feud with Fred isn't entirely one-sided, but Trent [[ http://www.gpf-comics.com/archive/2005/08/17 does eventually push the Team Dad too far.]]
In Gods Playing Poker, Cthulhu himself is generally on the side of hurting people and eating souls, although the actual group doesn't do much literal heroing, being mostly composed of holy figures of various faiths.
In Darths & Droids, Pete doesn't exactly play his character evil, but as more of an insane and completely ammoral psychopath. Though he doesn't seem to be aware that there is anything unusual about it. And it's R2-D2 of all people.
DM was also going to enter Kurahadol into the team, but instead illustrated some of the problems inherit to this; he was so excessively rude to his would-be party members that by the end of their first meeting, Luke was asking if they could just kill him off so she'd have to roll up a new character.
Many of the characters from Red vs. Blue can occupy this role depending on their current motivation. Sometimes Church; most often, Tex. After season 2, when the teams are frequently allied against a greater threat, Sarge views the Blues as a collective Evil Teammate.
Kirby from Sonic For Hire, who is a whole lot eviler in this series than he normally is. He doesn't mind swallowing or hitting innocent creatures or servants with umbrellas.
Even though Nights has happily tortured people in the past, Krauzer still takes this title in AJCO - he's a jerk to everyone, including his allies, and has revealed that he murdered the man who raised him and taught him all he knows because he felt he was 'getting in the way'. Also killed his own parents aged four, but even he doesn't know that.
Discussed in Counter Monkey, in which Spoony actively discourages letting a player make an evil character in a party of good guys since not only because the player simply just want to actively fuck with the party, there is no reason that a group of heroes would trust said character, especially if there's a Paladin or Cleric (who can cast Detect Evil) within the group. He does however offer some possible ways to make the character work (a Lawful Evil character or one who hates the current villain more than he does the party).
Bender: From now on I promise I'll never be too good or too evil again. I'll just be me. Leela: Do you think you could be a little less evil than that? Bender: I dunno. Do you think you could survive a 700 foot fall? Fry: Good old Bender.
Given his near-total lack of regard for human life and number of Doomsday devices, one could also make a case for Farnsworth being this.
It's more like Billy is the Token Good Teammate as the other two in the Power Trio are a morally bankrupt and apathetic being, and the Grim Reaper. Of course, Billy's behavior often bordered on psychopathic and insanely selfish, it's really just that Mandy is more generally malevolent.
And the only reason Billy could be considered good is because Good Is Dumb. Some episodes have Grim as the Token Good Teammate, depending how far Billy has gone this time (with Mandy keeping them in line for her own sanity and evil plans). You know how weird things are when the Grim Reaper is the Only Sane Man.
Both played straight and inverted in Total Drama All Stars. Inverted with the Villainous Vultures having Gwen (who doesn't even want to be evil) and played straight with Courtney and later Duncan on the Heroic Hamsters and Mike's new evil personality Mal.
Joseph Stalin in the "Freedom League" sketch on Histeria!!
Dinobot serves this role in Beast Warsfor about the first two seasons. Shortly after his death, Blackarachnia takes over.
Buford from Phineas and Ferb isn't actually evil, but he is rude, intimidating, and a self-professed bully.
Prince Phobos, the former season's Big Bad, takes this role briefly during the second season of W.I.T.C.H., because he's the only person who can take the new Big Bad's Amplifier Artifact away from her without it instantly teleporting back. Phobos spends a handful of episodes grudgingly helping the heroes (while acting like a titanic Jerk Ass to them all the while) and then he finally gets what he wants- said Amplifier Artifact for himself. He promptly betrays everybody and resumes the throne of Big Bad.
Word of God is that if the planned Gargoyles spinoff Gargoyles 2198 ever gets made, Demona, Big Bad of the existing Gargoyles series, will take this role. It's not that she's gotten over her Fantastic Racism towards humans, but more that she's decided she likes the Scary Dogmatic Aliens who've taken over Earth even less — for now. Whether she'll eventually morph into The Atoner or take back the Big Bad role herself is left deliberately unanswered.
Rabbit from Winnie the Pooh often acts as a child friendly variant of the trope. He is certainly the most antagonistic of the other docile members of the Hundred Acre Wood, he is a Grumpy Bear at worst however, and to many audiences the sanest and most relatable character of the series.
Rico from The Penguins of Madagascar. He's canonically classed by Skipper as their resident psychopath, and out of any of the members of the penguin team, causes the most trouble intentionally.
In Justice League episode Hereafter, when Superman was supposed dead, Lobo stepped up to fill in the missing spot. He took the Hero Insurance ridiculous to new levels. Of course, the other members of the league never agreed to it but they really needed an extra hand at the time. When Superman returns, they get Lobo to scram.
Trina Riffin from Grojband, and as much as being a hinderance to the band, she's also an unwitting help to them (Corey's inability to come up with lyrics is part of the reason).
Varrick in The Legend of Korra. His motives for helping Team Avatar against Unalaq were far from altruistic, as he did not care for the interests of the Southern Water Tribe, only for profiting from the conflict. He is willing to go to extremes, such as breaking the law to do this.
However, he ended up becoming a Sixth Ranger Traitor and he was sabotaging their mission from the start. He masterminded terrorist attacks behind the heroes' backs that were executed by triads. He even took advantage of Asami by stealing her equipment just to make her desperate enough to sell him controlling interest.