Matsudai is a classic Idiot Hero — impulsive, well-meaning, slightly self-centered everyman who's ultimately devoted to his True Companions. He spends the whole series opposing a serial killer, since he is a cop. He just so happens to be working against Villain Protagonist Light.
Soichiro until towards the end, and he is described by the author as the only one-hundred-percent good character. However neither he nor Matsudai are Light's direct antagonist as such, while L and Near are.
A few of the Marine Officers the main characters have to face are genuinely good guys who actually want to protect that public and don't view civilians and their own soldiers as being completely expendable. Notable examples are Smoker and Tashigi (who have practically achieved Friendly Enemy status with the Straw Hats), T-Bone (A Father to His Men), Coby (Luffy's old friend), Garp (Luffy's grandfather), Kuzan (a.k.a. Aokiji) and Issho (a.k.a. Fujitora).
One filler arc included the presence of a rational, normal Marine captain, who had no strange abilities or quirks, but was led by some crazy, immensely fat admiral and his equally stupid lieutenant, who where on par with all the early, lighter One Piece villians.
Commander Jonathan of the G8 filler arc. While he pursues the Straw Hats after they literally drop into the middle of his fortress, he offers mercy to the crewmembers that don't yet have bounties, refuses to treat his men as expendable, and has nothing but disdain for the visiting commanding officer that wants the Straw Hats captured no matter the cost.
Magellan and Hannyabal, the chief warden and vice-chief warden of Impel Down. Their motives are basically to stop the prison break (which was initiated by Luffy) and keep order in the prison.
Former Fleet Admiral Sengoku has done some... questionable things in the past (Ohara), but there is no question that he only does those things for what he feels is for the good of the world. And some part of him has always been suffering for it. He finally retired when the World Government decided to cover up the breakout of several Level Six Impel Down prisoners in order to save their reputation, instead of sending out warnings and wanted posters like he wanted to do.
The Wolkenritter. So here we have a group of "villains" whose malicious goal for filling up the Artifact of Doom was so they can save an innocent Ill Girl from certain death, and they were doing it in a way so they wouldn't kill or severely maim anyone. Problem was, due to reasons beyond their control, it wouldn't have worked without Nanoha's help. Either the Book of Darkness would have killed the girl and reincarnated elsewhere, or Admiral Graham would have frozen them both forever.
Admiral Graham himself. He's a Well-Intentioned Extremist who wanted to stop the Book of Darkness forever. Most previous masters of the Book of Darkness abuses it for their evil ambitions and they used the Wolkenritter as killers.
Inspector Runge starts out as one, though he turns to more of a standard villain for a while as his search for Tenma becomes more of a personal obsession than anything to do with justice, causing him to ignore the increasing evidence that Johan does exist. However, he eventually comes to his senses and becomes a hero again.
Eva Heinemann, whose Rich Bitch front and vengeful personality, as well as her contention that "not everyone is equal", belies her desire for a more fulfilling life. When given a choice between helping Roberto end Tenma's life or helping Tenma escape and survive, she chooses the latter, and, later in the series, her character development allows her the opportunity to work beyond her grudge, do the right thing and become a better person.
Zechs Merquise from Gundam Wing; after achieving his initial goal of revenge for the destruction of his homeland and the murder of his parents, sets about trying to realize their goal of a peaceful world — the exact same goal his sister Relena, the show's female lead, is going for. The major difference is that Zechs is a Well-Intentioned Extremist more than willing to hold the Villain Ball in order to scare the planet towards peace — and his personal pride keeps drawing him into battles with protagonist Heero.
Bleach: The entire Seireitei (sans Aizen and company) in the Soul Society arc, if you look at it from their point of view — they're giving out lawful punishment to a criminal, and Ichigo and friends are the equivalent of an armed mob raiding the police station to break her out.
The court in Seirei no Moribito. They only want to destroy the water demon that will cause a drought in the land, and none of them are very happy about the fact that the host has to die to do it. It's not really their fault that they don't know the true nature of the possession. They learn otherwise, which ends up aligning them with the heroes instead.
Ryuhou from S Cryed is less evil and more concerned with the welfare of most people than the Jerk with a Heart of Gold protagonist, Kazuma. About half of HOLY qualifies as this, because they either don't know how evil the organization is or believe that it's necessary to bring peace. And since Ryuhou and Kazuma get about equal screen time, Ryuhou is a joint protagonist — several episodes focus on his perspective. He evolves into a protagonist in the episodes following his second battle with Kazuma, but up until then he's just painted as a semi-peaceful well-meaning villain.
Hellsing: Father Alexander Anderson is a Noble Demon and Sociopathic Hero, sure, but he specifically targets vampires and heathens and attempts to keep civilians out of the line of fire, even forfeiting a chance to battle Alucard because of there being too many innocents in the museum. He despises rapists as well, and is willing to escort Integra back to Hellsing Manor "to protect her maiden virtue", which is quite telling after Villain Protagonist Alucard's encounter with Rip Van Winkle. Vatican Section XIII, the Iscariot Organization to which Anderson belongs meanwhile, goes well off the deep end in the manga and OVA by waging another crusade on bothMillennium and all of Protestant England, swinging them into literal Knight Templar territory. This highlights Anderson's own moral compass because he assists in killing his own boss/surrogate son for his crimes.
Team Unicorn and Team Ragnarok of Yu-Gi-Oh! 5Ds. But at least the protagonists aren't that bad.
Kira Yamato qualifies as one in Gundam SEED Destiny, against the Anti-Hero Shinn Asuka, until the supposed role switch after the destruction of Freedom Gundam.
Angel, a.k.a. Tachibana Kanade, in Angel Beats!. The whole thing was a case of Poor Communication Kills, and when they actually sit down and talk to each other they find they have no reason to fight anymore.
Kamikaze Kaitou Jeanne has Miyako, her best friend and pursuer, and Chiaki/Sinbad, who tries to stop her from helping the Devil because he is working for God all along.
By the end of Shakugan no Shana, Yuji Sakai with Snake of the Festival are this trope. They get to save the world and make the Flame Haze the bad guys without them knowing it.
Oswald/Glen Baskerville of Pandora Hearts revealed himself to be this and only wants to reverse the effects of what he believes his own naivety caused one hundred years ago. By going through with his plan he would erase a good many characters from the timeline but would also prevent the deaths of countless innocents. Unsurprisingly, Grey and Gray Morality abounds.
Shirakawa, initially a cold Girl Friday to Kurama, secretly she investigates the Director, and seeks to stop his experiments. Even after her death, her information informs her superiors, the Japanese Government of the experiments at the facility and they mobilize against the Director.
The Operatives hate Lucy, and they pilot the vector craft to attack the facility and kill any and all Diiclonius, and retrieve the cure to the disease, which has just been used to infect everyone in the world. They still have no problems with lying and shooting unarmed people as long as they complete their task.
The Agent is initially just a replacement field operative after Bando and The Unknown man were indisposed. She wants to save the world from the diiclonius virus. She opposes the protagonists, but honestly does not care about them, as they're all small in the grand scheme of things. She rescues Arakawa, who has the cure, and risks her own life to get the scientist to safety. Her motivations are notably without the self interest that almost every other character has, she just wants to do the right thing.
Argent the Wolf of Grendel, who's opposed to the Villain Protagonist Grendel (particularly Hunter Rose, but later on Christine Spar) as an Anti-Hero Werewolf who is compelled to take down what the series equates to the Devil.
The U.S. military is usually portrayed this way in Incredible Hulk, as they usually genuinely believe that the Hulk is a dangerous monster that they need to stop. Stan Lee commented in an interview that portraying them that way allowed him to get around The Comics Code's insistence that authority figures always be portrayed positively. Afterwards this changed, and there emerged a trend to portray General Ross, who usually commands the anti-Hulk military forces, as a General Ripper.
Most of Emp's jerkass teammates in Empowered, particularly Sister Spooky (although she becomes more sympathetic and less hostile towards Emp in the later volumes).
An early installment of Tintin has Nestor the butler as this. He's working for someone he doesn't know is evil, and for much of the plot he actively sabotages Tintin and the Captain.
In nearly all of their appearances, the Thompson Brothers are attempting to arrest Tintin and/or his allies for any assortment of supposed crimes. The only problem is, they're not very good at it.
Ord from Whedon's "Breakworld" arc in X-Men. He seems like an Always Chaotic Evil alien invader at first, but ultimately he's just trying to save his world from destruction. The only reason he is even opposing mutantkind in the first place is because of a prophecy planted by the real Big Bad that a mutant would destroy Breakworld. In the end, he makes a Heroic Sacrifice to save Breakworld from the true Big Bad.
Everybody in Red Fire, Red Planet alternates between this trope and some form of protagonist. It's a war story that presents characters on both sides of the Federation-Klingon War as protagonists when the story is told from their perspective and the enemy when the viewpoint switches to the other side.
Clopin becomes one near the end of The Hunchback of Notre Dame. Yes, everyone's favorite master of ceremonies, who is often cheerful and friendly, and suddenly become a cruel judge presiding over a Joker Jury in the Court of Miracles!
Captain Gantu in Lilo & Stitch is trying to capture a dangerous escaped experiment, who happens to be the main character's beloved friend.
Elsa the Snow Queen fulfills this role in Frozen in that she drives the conflict, accidentally creating an Endless Winter in the middle of summer when she runs away to the mountains to isolate herself in an attempt to protect everyone else from her powers. Her sister, Princess Anna, has to seek her out so that they could find a way to stop the winter she unknowingly caused.
US Marshal Sam Gerard (Tommy Lee Jones in the role that made him famous): The Fugitive. His quest is to capture the hero, who is a fugitive from justice, whether or not he's innocent of the charge. The character was popular enough to warrent a spin-off sequel, U.S. Marshals, which goes through a similar premise, but is actually starring Gerard.
Colin Farrel's FBI Agent brought in to investigate Pre-Crime in Minority Report.
Martin Prendergast in Falling Down. Unlike Bill Foster, who is on his violent rampage against the petty frustrations of modern society, Det. Prendergast tracks him down while constructively dealing with his own annoyances with empathy and maturity.
Most of the colonial officers and men (such as Commodore Norrington) that oppose Jack Sparrow throughout the Pirates of the Caribbean films, since they are trying to bring a wanted criminal to justice. Cutler Beckett is a total bastard though.
Iceman from Top Gun. He's a git, but he's on our side. He even has a point regarding Maverick being too dangerous. Really, all he wants is what's best for the navy.
Antoine Richis, in Perfume, played by Alan Rickman. Richis is an intelligent nobleman and loving father who tries to protect the city and his beautiful daughter from the protagonist, a serial killer who preys on virginal girls.
Brad Pitt's team in Inglourious Basterds are presented in this way, as for most of the movie, we are either following around their enemy Col. Landa or an entirely different plot.
Christian Bale as Melvin Purvis in Public Enemies spends the whole movie trying to stop Villain Protagonist John Dillinger. Interestingly, the film undercuts Purvis' competence and implies that Charles Winstead was the agent really responsible for taking Dillinger down. (According to some sources, Winstead may very well have been the agent who actually shot Dillinger.)
The Medjai function this way, at least at first, in The Mummy. While they attack the protagonists, it's only to stop them from awakening Imhotep.
Ditto for Kazim in Indiana Jones and the Last Crusade. He doesn't know Indy's intentions and just wants to protect the grail from falling into the wrong hands, and when the misunderstanding is cleared up, he helps out.
Jack Welles from Takers. While the bank robbers were the Villain Protagonists, he's a cop trying to stop them.
FBI Special Agent Adam Frawley fulfills this role in The Town. While he was very much a Jerk Ass and not quite as personally sympathetic as the Villain Protagonists, he was ultimately an FBI agent trying to shut down a ruthless and dangerous gang of bank robbers.
The Negotiator: Kevin Spacey plays a negotiator who tries to negotiate another (rogue) negotiator (protagonist Samuel L Jackson) out of doing something dumb after he holds up some hostages because he was framed for murdering his partner. As far as Spacey is concerned, Jackson is armed, has hostages and is therefore the villain.
The policeman Mitch from First Blood. Unlike the other cops he didn't bully Rambo, but still participated in the hunt for him. To a lesser degree, Col. Trautman, who knows and understands Rambo, and wants him brought in without bloodshed (partly because he alone knows just how much bloodshed will result).
The titular detective from Columbo was depicted this way in his initial appearance in Prescription Murder, the main Sympathetic P.O.V. being on the culprit with the detective not appearing till near halfway through the movie. However the series began developing Columbo's trademark whimsy and wise cracking persona afterwards and, while a lot of spotlight is still usually given to the suspects, Columbo eventually became the lead.
Tommy Conlon in Warrior. He opposed the protagonist for reasons unknown until the very end, an example of Good Versus Good.
The title character of the old western film Chato's Land, played by Charles Bronson. He is also The Voiceless, having only two speaking scenes in the entire movie – one, extremely brief, at the beginning, and one later in the film, shot entirely in the Comanche language, with no subtitles.
Pamela Landy in The Bourne Supremacy. In the next film, The Bourne Ultimatum, however, she helps blow the whistle on Operation Blackbriar.
The Winkelvoss twins and Divya Narenda in The Social Network. They're both snobs (Narenda being the Token Good Teammate), but the film depicts them as being in the right, since Mark did steal their idea.
The police chasing Maindrian pace in Gone in Sixty Seconds (1974). They're only trying to put a stop to a recent rash of high end car thefts.
The guards in Escape from Alcatraz, who are simply trying to contain a prison full of dangerous criminals. The only completely unsympathetic "good" character in the film is the Warden.
Dylan Rhodes and Thaddeus Bradley in Now You See Me. Subverted in Rhodes' case, as he turns out to be the Fifth Horseman.
Ed DuBois, one of the only characters in Pain and Gain that can be considered heroic, who is trying to solve the case of the Sun Gym Gang.
In Thor, S.H.I.E.L.D. is up until the end only screwing up things for both Jane's team and Thor himself. The audience knows they're good guys due to the comics and Iron Man movies, but for the protagonists they seem only like a bunch of intrusive jerks. Thankfully once Thor gets his powers back he states the agents were only misunderstood, and then they decide to help Jane's research.
Inspector Aberline from The Wolfman (2010). He's just a cop doing his job and trying to stop Lawrence from killing again.
Morgan from The Dresden Files, who watches Harry like a hawk, convinced that he's either a traitor to the White Council or just into Black Magic. At the same time, he's a warrior who will do anything to stop evil and protect the innocent. Eventually, he gets over his distrust of Harry; he still thinks Harry's a loose cannon, sure (and he's not exactly wrong, either), but he sees that Harry's trying to do good. Then, he dies.
Kariya Matou in Fate/Zero. His reason for entering the Grail War and deciding to endure horrible torture and surely die no more than two weeks after the Grail War ends to make up for his lack of training? Because he's the Unlucky Childhood Friend of Tokiomi Tohsaka's wife and he wants to save her daughter, because he knows pretty well what kind of magecraft the Makiri family perfected. Oh, and since he failed, just look what happened to Sakura in Heaven's Feel Route. Granted, his ending and last couple of actions aren't exactly very heroic, but yea, the motive was good.
Duke Michael in The Prisoner of Zenda. Unquestionably a better person and ruler than the legitimate king, and almost as good as the main character.
The Last Hero has this as a major plot point. Cohen and the Silver Horde are traditional fantasy heroes, but they are convinced their plan is bad once an honest man with a simple sword stands alone against them to stop it. This is mainly because they know they're traditional fantasy heroes.
Also a plot point in Witches Abroad, in which wicked witch Granny Weatherwax is the one aiming to stop a fairy godmother trying to force storybook endings onto people. During their encounter, said godmother insists that she's the Good One.
Played with in The Truth, in which the protagonist William de Worde (mind you, not a Villain Protagonist) finds his work as a journalist significalty complicated by one Sir Samuel Vimes, Commander of the City Watch. Most readers will know Vimes to be a thoroughly decent, if perpetually grumpy, person and, as such, can understand where he's coming from.
Moist von Lipwig has a similar relationship with Vimes. Lipwig is a criminal, and Vimes has every reason to be suspicious of him, but in this case he's actually attempting to accomplish something good.
Claude Lebel, the man assigned to catch the eponymous assassin of The Day of the Jackal. After Lebel is introduced, the plot stops following the Jackal exclusively, and is as much Lebel's story as it is the Jackal's, so Lebel goes back and forth between being a Hero Antagonist, and a straight Hero. The Jackal goes back and forth between being a straight Villain and a Villain Protagonist.
Ged, the protagonist from A Wizard Of Earthsea, serves as the Hero Antagonist to Tenar in the follow up book, The Tombs of Atuan. Tenar spends the entire book as a priestess to a cabal of evil spirits posing as gods, and when Ged clues her into that fact, she Heel Face Turns and sides with him — much to the chagrin of her old bosses.
Thot Keer in Zero-Sum Game. A Breen shipyard manager, his work crews are developing a prototype starship using stolen Federation technology, and the protagonist's mission is to destroy both prototype and shipyard. Keer is certainly not a villain, though; he is merely a patriot who takes pride in his work, and displays great bravery and (for want of a better term) humanity throughout the novel.
Praetor Gell Kamemor is a Romulan patriot opposed to the Federation politically, but she adamantly disagrees with the notion of Romulan superiority promoted by the Tal Shiar and much of the military. She would rather resolve the conflict with the Federation in the diplomatic arena than on a battlefield. All of her scenes in the series show her as a Reasonable Authority Figure compared to the previous cadre of conniving and backstabbing Romulan politicians.
The entire Jedi Order plays this role in the Darth Bane trilogy as the books focus on the perspective of the Sith Lord and his apprentice Zannah.
Roy Merritt in Daemon. Though we eventually know better, Sobol is a dangerous maniac who employs a menagerie of vicious sociopaths.
Porfiry Petrovich, the brilliant and implacable policeman investigating Raskolnikov, in Crime and Punishment.
In Please Don't Tell My Parents I'm a Supervillain, Generic Girl and Miss A are the only ones that come after the Inscrutable Machine on their own initiative — Generic Girl genuinely wants to stop crime (even their relatively harmless crimes), but Miss A is just a Jerkass. Mech, Ifrit and Marvelous all show up at different points to disrupt their supervillainy activities as well, but that's more secondary. Mech showed up to stop the Eldritch Abomination they unleashed, Ifrit got dragged in by Miss A and later Marvelous, and Marvelous was actually trying to steal the same thing they were at one point.
In the Daniel Faust series, FBI Special Agent Harmony Black is a straight-shooting, by-the-book crusader who practices witchcraft on the side. She's got a massive hate-on for anyone who uses magic for evil...which, unfortunately, includes Daniel Faust and most of his friends.
Live Action TV
In The A-Team, Colonel Lynch and later Colonel Decker and General Fullbright all fill this role. Although they oppose the A-Team they're not evil or corrupt. They're good soldiers who are following orders, and they honestly believe that the A-Team are dangerous criminals that must be brought to justice (which is not an entirely unreasonable assumption).
In the Angel episode "Sanctuary" Buffy becomes this. She wants to kill Faith; it doesn't matter if Angel wants to redeem her. The former lovers even come to blows because of it, and part on bad terms.
Agent Hank Schrader of Breaking Bad. Something of an interesting case in that he doesn't know the Villain Protagonist he's chasing is his own brother-in-law ...until the middle of the finale season.
Season 1 has two FBI agents tasked with making Michael's (who was "burned" and turned into a villain in the eyes of most of his fellow co-workers) life miserable, and also Jason Bly, a CSS agent who takes up the cause when the FBI backs off.
Detective Paxon in the beginning of season 3 is a sqeaky-clean, by-the-books cop (when Michael & co try to figure out how to blackmail someone and can't, you know they're clean) who is a little tired of Michael blowing things up in her city.
Dani Reese in season 5 is hunting for a killer. Too bad Michael has been framed very convincingly to look like said killer.
Lee Jin Pyo in The City Hunter: His entire black ops team was murdered by their own government,who first denied their existence and then branded them as traitors. As he's a "dead man," he can't work/live in his native Korea. He just wants to expose their corruption and get revenge on the ones who ordered his team's execution.
Sergeant Doakes, though his morality is called into question a few times. Somehow, he's the only one in a precinct full of cops and forensic specialists to get a creepy vibe off serial killer protagonist Dexter. This doesn't end well for him.
Special Agent Frank Lundy in the second season. He probably would have caught Dexter if it weren't for Doakes' suspicious and secretive behavior making him more conspicuous than Dexter.
Detective Quinn is set up as this in season 5. He's the only one in the office who notices that the Mitchell family's sketch drawings of "Kyle Butler" look a lot like Dexter, and starts to suspect that Dexter may have killed Rita, his wife. At the end of the season, he abandons his investigation when Dexter gets him off the hook for a murder that Quinn is erronously suspected of (in fact, Dexter himself committed the murder), and he falls in love with Debra.
Stan Liddy in season 5. Although he's a Dirty Cop, and is trying to expose Dexter mostly for his own benefits so that he will be reinducted into the police force, he is still trying to catch a serial killer. Dexter kills him, and Quinn is subsequently suspected of the murder.
Maria Laguerta in season 7. She discovers evidence that may expose Dexter as the real Bay Harbor Butcher, and starts her own investigation. Dexter tries to kill her, and Debra shoots LaGuerta to cover up for her brother.
In the second season of Dollhouse, Senator Daniel Perrin tries to expose the corrupt Rossum corporation, the Dollhouse's main benefactor. Until it turns out that he's a Doll imprinted to investigate the Dollhouse so that he can "discover" convincing evidence that it doesn't exist and exonerate Rossum.
Peacekeeper Commander Scorpius of Farscape swings somewhere between here, Well-Intentioned Extremist and Villain Has a Point. His one driving goal is to stop the advance of the Scarrans, a brutal and murderous race who are known to have ordered a systematic raping of women from another race to guage whether it was worth keeping them alive as breeding stock (answer: no, because the halfbreed physiology kills the mother and normally the child on birth) and to be willing allies with the Charrid (a race of Orcs In Space who are infamous for attacking the harmless Hynerians and devouring 80 million of their young before being driven off by waves of suicide attackers). He believes the key to this is mastering wormholes, via information locked in the brain of the human John Crichton. To this end, he is willing to chase Crichton to the ends of the galaxy and Mind Rape him into giving up this info, though this is only because Crichton will not countenance simply cooperating with Scorpius and giving him the wormhole technology peacefully.
Most of the less-developed alliance officers in Firefly, who are unaware of the alliance's atrocities and are just trying to capture a band of criminals.
Many of the antagonists are just working to bring down King Uther, who is undoubtably a tyrant.
Arthur occasionally lapses into this. While he's undoubtedly The Hero, he has been raised from birth to be distrustful of magic and will not hestitate to arrest anyone caught using it, even though the penalty is death. What seperates him from Uther is that he does this not out of maliciousness, but because it is his Father's law and he's honour bound to obey it.
Agent Victor Henriksen on Supernatural spends the better part of two seasons chasing Sam and Dean Winchester, believing them to be dangerous serial killers. He's a good agent and a good guy, but doesn't know that he's living in a Crapsack World where things like demons and skin-walkers exist — eventually he finds out in his last appearance on the show.
24 has CTU or any other law enforcement agency whenever Jack Bauer has to go rogue or is set up (which is a lot)
Wizards of Waverly Place is driven by the three protagonists being this for each other. Even so with Alex, whose the nearest the series has to a reccurring main villain, and her by-the-book brother Justin.
Older Than Feudalism: Hector in The Iliad. The Trojans are portrayed far more sympathetically than the Greeks, Achilles finds redemption instead of punishment at the end, and the narrative ends with Hector's funeral. At the end of the day he's trying to defend his home over his brother's folly and the Greeks' warmongering.
Charlie, the anvil salesman, from The Music Man. He's trying to expose a con man looking to run off the townspeople's money and, as result, makes doing business impossible and even dangerous for the legitimate salesmen who follow.
Agent Edgar Ross from Red Dead Redemption. At the core, he wants to bring law, order, and civilization as well as round up all those who seek to destroy it. Were he not the antagonist, we would likely think he's onto something, perhaps even root for him in secret. However, this is subverted at the end, when he chooses to forgo his deal with John and raids his farm, killing him anyway. When Jack hunts him down post-game, he shows no remorse, and blames John's death on John himself for even choosing to be an outlaw in the first place, despite his desire to change for the better.
Cyrus Temple from Saints Row: The Third. His evil plot? To restore order by stopping gang wars. You are a member of a gang, and thus that makes him the antagonist. Were this any other game, he'd be the good guy.
In Deus Ex, after you defect from UNATCO, any cop or U.S. or UNATCO soldier that truly believes he is fighting for the greater good and is not flat out sadistic or part of the conspiracy, fit this trope.
A smaller example in Deus Ex: Human Revolution for the police station level. If you don't talk your way in and either sneak in through the back, or shoot your way through, the Detroit police serve as this. They are not aware of the conspiracy surrounding the dead hacker; they're just following orders.
Hakumen from BlazBlue, one of the Six Legendary Heroes who saved the world from the attack of The Black Beast. He wants to prevent a rebirth of The Black Beast by killing Ragna. He is not open to alternative solutions. However, in quite a few character's stories — Taokaka's and Bang's, for example — he pretty much attacks them because he can, and he doesn't hold back at all; in Bang's case, if the player loses the "bossfight" against Hakumen, Bang actually dies of the injuries Hakumen inflicts on him, even though at their power levels, Bang is practically no threat to him at all. Also, like the actual Samurai, Hakumen possesses a bizarre and at times quite brutal view of "justice" that makes sense only to him, which justifies many of his clashes with other good characters. Hakumen is a textbook example of Good Is Not Nice at his best, and an actual villain at his worst.
Jowy Atreides, from Suikoden II. A long time friend of the main hero, Riou, he is destined to come into conflict due to picking up opposing runes (Jowy picks up the Black Sword Rune and Riou the Bright Shield Rune). Jowy ends up betraying and murdering (although not willingly) the mayor of Muse, Anabelle. He ends up becoming king of Highland. He ends up as a Hero Antagonist because he helps bring down Luca Blight, as well as using his strength to keep the Beast Rune at bay. He ends up having the same goals as Riou, to end the war and to unify the land. The problem is that he and his friend, Riou, lead opposing forces. His love of the orphan Pilika truly drives Jowy in his goals for peace.
Thorndyke from Soul Nomad. Also, everyone but the monsters in the Demon Path.
Meta Knight from the Kirby series, who usually only fights the pink puffball to stop him from inadvertently unleashing the sealed evil of the week. Also, King Dedede in Kirby's Adventure, whose bid to seal the evil of the week by removing the Star Rod from the Fountain of Dreams was misinterpreted as villainous by Kirby.
Harpuia from Mega Man Zero. He even prefers to be destroyed than to be possessed by a manifestation of evil in the second game. By extension, Harpuia's fellow Guardians, Leviathan, Fefnir and Phantom, as well as all of the Bosses prior to Zero 3. They were only following orders for the sake of protecting humanity. No longer really applies as of Zero 3, at least for Leviathan, Fefnir, and Phantom, as all three are stated to have stopped caring about anything other than their obsession with defeating Zero.
Knuckles in certain games, in particular those where he is tricked by Dr Eggman into stopping Sonic. He eventually realises he has been duped, and usually reverts to a side protagonist for the remainder of the story.
Velvet from Odin Sphere, against both Ragnanival and Ringford. Given Gwendolyn and Mercedes are guilty of most of the incidents of Nice Job Breaking It, Hero in the story (Velvet causes very little herself), she's rather justified.
Gordon Freeman and Cpl Adrian Shepherd are the protagonists of different Half-Life games, working to opposing ends. Shep wants to catch Freeman, for starters, and Freeman has nuked a number of soldiers.
Subverted in Disgaea 3. Mao is a Villain Protagonist (Noble Demon type), and Super Hero Aurum is originally portrayed as some legendary super hero. The subversion occurs around Chapter 8, when the player discovers that Aurum is nothing but a big phony who's so foul that even demons scorn him (especially his transformation).
In one Rikti War Zone/Vanguard arc of City of Heroes, rival organization Longbow becomes full-on Hero Antagonists. In sister game City of Villains Longbow is only one of many such organizations, thanks to the Villain Protagonist nature of that game's characters.
The Queen Fay and the Elves of the Everlight Sanctuary in Overlord II, even though the Elves are, for the most part, whiny hippies concerned mostly with protecting cute and furry creatures. Eventually, while sacrificing her energy to help the Overlord defeat The Empire, she is corrupted by his magic and becomes a Fallen Hero who decides that Evil Feels Good.
Persona 4 has a subversion with Taro Namatame, who started kidnapping people after the death of Saki Konishi due to being tricked into believing that TV World was a shelter from the true killer, not knowing that all the characters were saved due to the efforts of the Main Character and his friends. The player can either punish him by tossing him into the TV and letting him get slaughtered by Shadows, or hear him out, where they will learn his side of the story, and he, in turn, will understand what he's done and willingly accepting the consequences.
The Metal Gear series is so full of lies and deceptions (and lots of RetCons very well disguised as such) that you can never really tell who is on which side, or even which sides there are. The prime example would be The Boss in MGS 3 whose heroic identity is only revealed after being killed by the protagonist.
In Imperishable Night the Stage 4 boss is either Reimu or Marisa, the two standard protagonists, who will blame you for the current incident and attempt to stop you.
In Mountain of Faith Sanae didn't know the Hakurei Shrine was key to Gensokyo's survival; she saw competition for the faith her gods needed to survive, from a Miko who wasn't even protecting humanity from the youkai. So she tried to shut down the Hakurei Shrine, and got her ass (and her gods') kicked.
In both Immaterial and Missing Power and Scarlet Weather Rhapsody, almost every character ends up fighting either Reimu or Marisa at some point in their story mode.
In Undefined Fantastic Object, the ancient mage the antagonists were trying to unseal turns out to be a Buddhist monk seeking to bring peace and harmony to Youkai. And she still fights you as the final boss.
The Watatsuki sisters, Toyohime and Yorihime, from the Spin-Off manga Silent Sinner in Blue. They're just trying to protect their home from invaders, with Reimu implicitly threatening to kill everyone on the moon at one point to make Yorihime take the fight seriously, and admits she will probably lose to Yorihime because the bad guys always lose, and they are the ones at fault in that incident. But because of the way the narrative is presented along with their Fantastic Racism, many readers came away thinking them as villains.
In Hopeless Masquerade Kokoro is actually trying to stop the Hate Plague, because it's her Power Incontinence that's causing it. Meanwhile all the other characters are trying to exploit it for their own ends, be it to advance the power of their shrine, as an excuse to beat people up, or just to mess with people for giggles.
General Warfield in StarCraft II, in stark contrast with his predecessor Edmund Duke. The literally only reason Warfield is featured as an antagonist in some missions is because he is working for ArcturusMengsk. Other than that, he puts The Men First, is concerned about protecting the population of the Dominion and is remarkably brave. While he initially isn't happy when Prince Valerian asks him to collaborate with Jim Raynor, they get along quite well after getting to know each other. His death screamsAlas, Poor Villain.
Some parts of the campaign in Warcraft III and its expansion have the player control a villainous army, making the enemy army a Hero Antagonist. This is most blatantly during the Scourge campaign, though the Horde and Night Elf campaigns tend to paint heroes from other factions in this light as well.
Depending what faction you play, certain NPCs in World of Warcraft will come off this way. For example, in Icecrown Citadel, the two factions fight each other aboard their respective airships, each one lead by a notable hero from each; Muradin Bronzebeard for the Alliance, and Varok Saurfang for the Horde. Both are well-respected and honorable figureheads within each faction and both seek to climb Icecrown to stop the Lich King, but tensions between the factions force them into combat with one another.
Araman from Neverwinter Nights 2: Mask of the Betrayer. From his point of view, unless the protagonist can be stopped somehow, the world will end. And, Okku, for pretty much the same reason. However, if you decide to spare him after the final fight against him, he'll decide to help you.
Riku serves as one in Days, where the story is told from the perspective of a Punch Clock Villain working for the bad guys.
In Sin and Punishment: Star Successor, The Nebulox are fighting against Isa and Kachi to help the humans of Earth-5. Also, from their perspective, Kachi is a major danger to their entire civilization — she was originally sent to Inner Space to recon Earth-4 for attack, but lost her memory.
Axel Almer in Super Robot Wars Original Generation in the enhanced remake becomes a Noble Demon whose greatest concern is to defeat a monstrous man (Beowulf) responsible for numerous atrocities in his (Axel's) home world. Even moreso in The Anime of the Game, where said monstrous man's first scene involves crossing the Moral Event Horizon. Then, in the opening credits, Axel fights off the main character (Kyosuke), under justification that he won't let another Beowulf be created from Kyosuke (Beowulf is Kyosuke's Alternate UniverseEvil Twin). By the time of the Gaiden Game, he drops the 'Antagonist' part while keeping the same goal (growing an 'Anti' in the front instead due to not being officially in the protagonist team).
Ash from Atelier Iris 3 simply wants to use the Escalario to stop Uroborus from awakening. To do this, he tries to kill Edge and Nell, and kidnap Iris, the only person able to use the Escalario.
Saladin, the captain of the guard at the Castle of the Crown in King's Quest VI, is perhaps the noblest of all the characters in the game. He has an antagonistic role only because he has been deceived by Alhazred and has a strong sense of duty regarding his job, and he does eventually wise up.
Alakazam and his team in Red/Blue Rescue Team. When the protagonist and teamate end up being tossed into exile, Alakazam and his team are the leaders of the hunt for the protagonist's head.
Palkia in Explorers of Time and Darkness, who thinks that the hero is threatening to destroy the universe. It turns out that he was tricked: Darkrai was the one threatening to destroy everything, and he made it look like it was the hero's fault.
In the first Max Payne, Lt. Jim Bravura and the rest of the NYPD. In the 2nd game, Bravura becomes Da Chief.
The freeware indie game Akuji the Demon has the final boss being the hero who defeated and banished you into the dungeon.
Wiegraf is one of these during the prologue of Final Fantasy Tactics and remains so to a lesser extent, later in the story. He starts out as a Holy Knight fighting against the aristocracy for very justifiable reasons. His only really even vaguely selfish or villainous actions are his attempts to take revenge on Ramza for killing his sister, but Wiegraf also doesn't know that Ramza tried to avoid killing her. Wiegraf later becomes a Fallen Hero, however, as revenge drives him off the slippery slope.
Battle for Wesnoth features campaigns like Descent to Darkness where many antagonists are heroes trying to defeat the necromancers.
In Fallout 3 the Brotherhood of Steel becomes one if you destroy the Citadel. The Regulators will hunt down the player if s/he has Evil Karma.
The censors in Psychonauts are mental antibodies. They're supposed to stamp out foreign influences. Like normal antibodies, they can't really distinguish things except as "native" and "foreign", even if "foreign" is a friendly psychic.
The Knights Templar in Immortal Souls are definitely good guys, as the only group actually devoted to actively fighting the "shadow creatures", which are almost all malevolent and/or mindless and devoted to harming humanity. But since they have a hard time accepting the "almost" in the "almost all" — and their leader is a major Good Is Not Nice jerkass to boot — that brings them into constant conflict with the two good vampires that are the main protagonists.
White Knight Leo from Lunar 2, in the early-going.
Unlike the original film TRON, security programs in TRON 2.0 are not servants of the evil MCP. Here, they're simply doing their job of protecting the system from The Virus. Unfortunately, Kernel, the chief security program, thinks you are the cause of the infection and tries to hunt you down, forcing you to fight security programs.
Balthazar from Baldur's Gate II: Throne of Bhaal, who, unlike most of the Bhaalspawn who are trying to seize the former God of Murder's power, is actually trying to rid the world of Bhaal's taint by destroying all other Bhaalspawn and then committing ritual suicide. If you're playing an evil character, he's got a good point. Sadly, if you're good, you can't persuade him that you can handle Bhaal's power without turning evil and he attacks you anyway. (One of the design directors for Throne of Bhaal did a mod, Ascension, where this becomes a possibility. You can even turn him into an ally for the final battle.)
Imperial characters in Star Wars: The Old Republic will face a number of these: good, honorable Republic forces and Jedi looking to protect the galaxy from the Empire. This is complicated by the fact you can play any character as Light (good) or Dark (bad).
In Syberia a disillusioned office worker tells her husband and employers, over the telephone, that she is going into the arctic circle, unprepared, to look for a fairy tale. The private detective chasing her for most of the story is trying to save her life.
Loghain from Dragon Age: Origins is a bona-fide hero of Ferelden, fighting only to keep the realm independent of any foreign influence, particularly Orlais (which had ruled Ferelden with an iron fist for quite some time). He was a faithful right hand to king Maric, and thought up most of the winning strategies in the king's war of independence. The only problem is that he does not understand (nor wants to understand, apparently) the threat of the Blight nor the importance of the Grey Wardens, and therefore every action he takes inadvertently weakens his beloved kingdom, which is why the player's team must stop him.
The Eldar in the original campaign are trying to stop a powerful daemon from being unsealed. Being Eldar however they never actually tell anyone this is their plan, and the Blood Ravens kill them in order to progress in their mission.
Dark Crusade, depending on which faction the player picks, can have them go against the Eldar (fighting to stop the Necrons from being unsealed and stopping anyone who would unseal them, even accidentally), the Imperial Guard (liberating the humans of the world from alien oppression), and/or the Tau (defending their colony world from alien invaders). Space Marines Vs Imperial Guard plays this for maximum tragedy, as they're both Just Following Orders and cannot back down. The Space Marines themselves however are not an example, as they're only fighting to conceal incriminating secrets from their Chapter's past.
Soulstorm has the same "Risk"-Style Map as Dark Crusade, with the Imperial Guard, Tau and Eldar making reappearances, and the Space Marines are actually heroic (if incompetent) this time. The Sisters of Battle are a blurry case; they're fighting to rid the Kaurava of all Chaos and alien taint, but their solution is to kill everyone and let the Emperor sort them out.
In Dawn of War II the Eldar are trying to stop the Tyranid swarm just as the Blood Ravens are; unfortunately their plan involves luring them onto the planets and then blowing them up, while the Blood Ravens are trying to save the planets.
Retribution bizarrely only has this for the tutorial mission for the evil factions (Orks against Eldar, Chaos against Space Marines, Tyranids against Imperial Guard), and one mission where the player fights a bunch of Eldar trying to stop the Exterminatus (which the player only learns after the fact). For every other mission the player fights against evil aliens or Chaos-corrupted renegades no matter which faction is picked.
Berk appears at first as Gwynn's weird and annoying new boyfriend, but then, in the chapter "K'Z'K", tries to assassinate several main characters — because he's been sent from the future to stop them from causing The End of the World as We Know It by summoning the demon K'Z'K.
Othar Tryggvasen (Gentleman Adventurer!). His stated goal of killing all the world's Sparks, ending finally with him committing suicide, appears to place him squarely in the realm of being a Villain with Good Publicity. It is only when one looks at how nearly every Spark he has ever encountered has acted that it becomes clear that his actions are fully justified. In one possible future timeline, his failure to complete his self-appointed mission results in the apparent eradication of human life in Western Europe, apparently within a few years of the main storyline. On the other hand, his twitter has him killing a college student and her father (because she was a spark and he said that the worst thing that could happen to a parent is their child to die before he did), derailing a train and becoming a Cop Killer.
Klaus Wulfenbach is almost the Only Sane Man in Europe, which means that he's got to play whack-a-mole with every crazed Spark or creation that gets loose. He is half-rightly convinced that Agatha could be the Biggest Bad of all time — the spark that destroyed most of Europe while he was removed from the picture decades ago and who may have the secrets of time travel on top of a host of other horrifying technologies. If he's right, he has to destroy her to save the world. Unfortunately, he doesn't have the full picture, and the pieces he knows look really bad for Agatha. Of course, as Agatha is the protagonist, she isn't about to tamely sit down and let him hold her.
Everybody has an "Evil Twin", right? Well, these guys see our Weatherlight crew as theirevil twins and act accordingly. They're not villains, per se, but everybody hates them.
Last Res0rt features Jason Spades, a hero on his home planet of Fenirel who happens to want to viciously kill Daisy to the exclusion of everything else, even if 'everything else' is something like getting the rest of the crew (including himself!) off an enemy ship alive.
In the Whateley Universe, the Reverend Darren England, protector of the planet from demonic threats for decades. He's willing to deal with The Syndicate if it means the death of The Kellith, the descendant of a Great Old One, before The Kellith can destroy all life on earth. The only problem is that The Kellith is Carmilla, who is an Anti-Hero protagonist and is trying to go straight.
The Insurrectionists/Charon Industries are this in the prequel segments of Red vs. Blue, in opposition to the Freelancers, who are Villain Protagonists at that point. Though, when we see the leader in Season 7, they've killed the excavation team at Sandtrap, and are trying to get their hands on Ancient Alien weaponry, so they might not actually be the good guys, just a different group opposed to Freelancer.
Zetto from TOME. It turns out that throughout Season 1, his goal has been to surpress and erase the Forbidden Power by hiring hackers to find it/steal the necessary resources to seal away the Forbidden Power.
Tim from Marble Hornets temporarily becomes this towards the end of season 3, as Jay begins to become less stable and more paranoid.
Dib from Invader Zim is between a Hero Antagonist and Deuteragonist. A paranormal investigator trying to prevent the alien Zim from taking over the world, there are numerous Villain Episodes where Dib is the main character, making him the protagonist (and usually casting Zim as the antagonist) a good portion of the time. He and Zim team up almost as often as they fight, and a fair number of episodes are about Dib dealing with other stuff while Zim makes only a cursory appearance.
Kyle usually serves this when an episode focuses on Cartman, because he's the closest thing the show has to a moral compass. Expect there to be traces of He Who Fights Monsters.
Kenny takes this role in "Poor and Stupid", because Cartman's antics as a NASCAR driver are tarnishing the sport's reputation, and Kenny loves NASCAR. Similar to Kyle however, he reverts to such overzealous extremes as trying to shoot Cartman with a rifle.
The Road Runner is one of the most iconic Hero Antagonist of Western Animation; the shorts granted little character to the bird outside his fast speed and his trademark "Beep Beep", and all sympathetic spotlight was deliberately kept on its predator, Wile E. Coyote.
Bugs and Speedy occasionally leaned into this trope, with many of their respective shorts focusing more on the blundering of their foes.
In "Fresh Hare", Elmer Fudd is only chasing Bugs because he is a mountie and Bugs has been charged with crimes. In "Big House Bunny", Bugs escapes hunters but ends up tunneling into a prison. Yosemite Sam is the guard and only goes after Bugs because he believes Bugs is an escaped prisoner.
In some Daffy Duck cartoons, Porky Pig is an authority figure such as a police officer trying persuing Daffy for his antics. While the nature of some of his "crimes" can be rather disproportionate (in "Daffy Doodles" for example he becomes Public Enemy Number One for painting mustaches on advertisement posters) Porky is clearly the higher moral ground.
The Yankee Doodle Pigeon of Dastardly and Muttley in Their Flying Machines was implied to be of heroic alliance, delivering important messages to squadrons. However, his role rarely exceeded outside blowing his patriotic trumpet and giving bewildered glances to the Vulture Squadron's blundering attempts to "Stop That Pigeon".
Ranger Smith from Yogi Bear. All he's trying to do is keep Yogi and Boo Boo from stealing food from the campers at Jellystone Park. A few cartoons show that he cares for them and gets upset if he thinks they're in trouble.
Xander Crews from Frisky Dingo, also known as the superhero Awesome X. He's also one of the biggest dicks in a show made almost entirely of dicks, sometimes more than Killface himself (who kills one of his PR reps in the first episode and then uses the guy's remains as a ventriloquist dummy in front of his twin brother).
Top Cat: Officer Dribble, er, Dibble. The protagonist, T.C., is a con-artist and leader of a street gang! Of cats.
The Centauri Empire officers in the Teen Titans episode Sisters only attacked the Titans due to misunderstanding that they thought Starfire was committing a thievery on their solar system when in truth, Blackfire was the one doing it and framed Starfire for it. Once that was cleared off, they successfully capture Blackfire and then never threatened the Earth anymore, therefore they're pretty much their planet's good police doing their job. Their conversation also kinda imply this:
Officer: In the name of the Centauri Empire, you are all under arrest! Beast Boy: Uh... you can't be the good guys. We're the good guys. Officer: And we are the Centauri police!