Edgar Ross and Dutch van der Linde from Red Dead Redemption. Both are fighting for what they believe to be best for society, Ross for civilization and Dutch for anarchy, and both display a complete willingness to Shoot the Dog if that's what it takes to get there. But the game shows that both of them are hypocrites and neither of their plans are without flaws anyway. The only real difference is that in the end, Ross is remembered as the hero and Dutch as the vicious outlaw, but then the game points out that had more to do with civilization ultimately triumphing and history being Written by the Winners then any real moral superiority of one over the other.
Emiya Shirou and Tohsaka Rin from Fate/stay night are foils to each other. Shirou is a mediocre and unorthodox magus that has to rely on determination, perseverance and his own cunning in order to make it through the holy grail war, with his desire being world peace. Rin is a rare genius magus that only shows up once every century due to her incredible magical potential, with her main desire being proving she is the strongest. Due to having some mutual respect towards their differences, (and both of them being the most ethical characters in the series despite what Rin might led you to believe) they always end up working together regardless of the route and end up making up for each other's weaknesses. It's to the point that they stop each other when the other one is about to do something risky. Due to the extremes in which a magus follows his ideals, they always put themselves on the line for their goals. Rin always stops Shirou when he is about to do something reckless out of his own selflessness, serving as his superego. And Shirou is usually the one who ends up stopping Rin when she is about to do something unethical and against what she really thinks because she is acting through her jerkass magus facade. (Rin always tries to fool herself into thinking this is her true self) Despite what she might say, It's obvious she respects Shirou enough to the point that she is willing to listen. Also yes, there is a lot of romance sub-text between the two, becoming a couple in the UBW route and the whole reason why they fall in love with each other is because of the mutual respect that they have towards their similarities and differences.
First is the rivals, gain their starter from the same place as the protagonist, go on parallel journeys and are often the few trainers that get a varied team in contrast with the mono-flavored teams everyone else has.
Many Pokémon species are foils to each other, most notably the version mascots and version exclusives for each pair of games.
Magikarp and Feebas are a good example of cross-generational foils. Both start out as weak fish with limited movepools but evolve into powerful serpentine Pokémon with enough effort. However, while Magikarp's evolution Gyarados is focused on brute force and is perpetually angry, Feebas evolves into the beautiful and tranquil Milotic, and while Magikarp is found in almost every body of water, Feebas is limited to a single route per game.
The man-made Legendary Mewtwo and Mythical Genesect are also foils to each other. Both created to harness the power of the ancients from a remaining piece of DNA, and both are a warped reflection of the being that they where created from (Mewtwo is more masculine to the androgynous Mew, Genesect is a cyborg with a cannon) and have opposite types. Where Mewtwo is a Blood Knight in the games and has a mostly special based movelist, Genesect is obedient to whoever controls it and has a physical based movelist. Its implied, both in universe and out, that this was deliberate.
Pokémon Sun and Moon has Kukui and Guzma, who had given up to become Trial Captains note Alola's version of Gym Leaders. Kukui decided to use his talents to instead become a Pokemon Professor, while Guzma instead lost hope and founded Team Skull.
Dr. Eggman is the scientist who wishes to rule through technology and a tyrannical, totalitarian rule which contrasts Sonic's nature-loving free spirit.
Knuckles is the Blue Oni to Sonic's Red, his strength to Sonic's speed, and his duty as guardian of the Master Emerald contrasts Sonic's carefree "go where I please" lifestyle.
Shadow is the deadly cynical and serious lethal enforcer contrary to the fun-loving adventure seeker in Sonic. While both hedgehogs are heroes, both of them have contrasting methods on how to take action which usually ends in both of them fighting each other.
Blaze is very introverted and devoted to her duties as a princess and guardian of the Sol Emeralds while Sonic is very extroverted and free-spirited. Despite their differences, or perhaps because of them, they get along very well, and develop a strong bond.
Eggman also contrasts with Sonic's sidekick Tails: both love to tinker with machinery, but Tails uses his skills to help his friends while Eggman only acts in his own interests. Tails also acts very mature for a 8-year old having the occasional kiddish moment to remind you of his age, while Eggman appears to be in his middle 50's but acts incredibly childish and immature.
Mario is a humble, adventure loving hero who always has in mind the means to help other people. Wario is a greedy and arrogant Anti-Hero who is always looking out for himself, despite not being that bad overall.
The Mario brothers are also foils to each other, since Mario is bold and adventurous, while Luigi is timid and cowardly.
In a similar manner, there is also Princess Peach and Princess Daisy. Peach is usually elegant, classy and quite polite. Princess Daisy on the other hand, is characterized as ultra-competitive and is generally full of spirit. Peach's usual role in most of the games she appears in is that of the Distressed Damsel while Daisy has only been one once.
Rosalina can also be seen as another foil for Peach. Whereas Peach is a peppy princess of the Mushroom Kingdom with Toads as her loyal subjects, Rosalina is more of a High Queen who travels the stars in a Comet Observatory with the Lumas as her children. She has also never been captured by any evil forces (yet her ship did lose power and became stranded once).
Yoshi and Birdo are two dinosaurs of Ambiguous Gender that regularly interact with Mario and friends. Yoshi is an egg-laying dinosaur that is more than happy to give Mario a ride on his back and is one of his closest friends. While he technically doesn't have a sex (or is both), he's often thought of as male. Birdo on the other hand, is an egg-spitting dinosaur that has an alignment that is all over the map. She may be friendly in one part of the game while a boss character in another. She's been implied to be Transgender, and identifies as female.
Master Hand and Crazy Hand from Super Smash Bros. are both foils to each other, but Master Hand is relaxed, peaceful, analytical and quiet while Crazy Hand is enthusiastic, active, short-tempered and irritable.
In Shadowverse, Odette and Odile, the White and Black Swans of Swan Lake, have mirrored stats, flavour texts, and voice lines. They even summon their rival under the enemy's control. Obviously, their color themes already give away their differences.
Fable III: Reaver is an Faux Affably Evil owner of an Industrial firm that uses child labor, and routinely shoots his workers for a variety of reasons. Once the player becomes the Ruler of Albion, Reaver recommends almost every evil option in the game. Page, the leader of the Bowerstone resistance, detests child labor and the abuse of the workers of Bowerstone. While Reaver disregards the lives of Bowerstone's citizens, Page fights for them. Page's Good Is Not Nice demeanor is the opposite of Reaver's Faux Affably Evil nature.
For many of the judgements as the ruler of Albion, its Page stating her case against Reaver. In the first half of the game, much of the antagonism between the two is shown, especially in the emansion sequence.
Sol Badguy and Ky Kiske in Guilty Gear: Sol is older, cynical, Tall, Dark, and Handsome with red eyes, Brilliant, but Lazy, wears red, uses fire, and has connections & motifs with darkness. Ky is younger, idealistic, a blonde Bishōnen with blue eyes, by-the-book, wears blue, uses lightning, and has connections & motifs with light.
Their Spiritual Successors, Ragna the Bloodedge and Jin Kisaragi follow the same mold with the added complication that they're also brothers. Despite growing up together, they end up leading very different lives; Ragna is brash, outspoken, and has one hell of a Hair-Trigger Temper and is considered a destructive force of nature because of his powers and his crusade against the ruling government. Jin is The Quiet One and prefers to avoid unnecessary fights as he considers them "obstacles" and is hailed as hero by the same government and determined. In their end, their paths and ideologies constantly put them at odds with each other.
Darkstalkers has Donovan Baine and B.B. Hood, both of whom are professional hunters. Donovan himself, is half-vampire, but hunts demonic monsters to protect all of humanity while struggling with the impulses that his dark blood threatens to bring about. B.B. Hood is the only human character in the roster, but beneath her innocent Red Riding Hood looks, she is wicked, sadistic, selfish, and downright evil, enough that even demons dread her. Her reason for hunting monsters is similarly because she is Only in It for the Money.
In World of Warcraft King Varian Wrynn is a foil to Warchief Thrall. Thrall is an orc raised by humans, with the cunning and patience more associated with humans, while Wrynn was forced to fight in orc gladiatorial matches, giving him a bloodlust and vendetta against orcs, things found in orcs more often. Their histories also mirror each other's (Thrall had his clan destroyed when the humans defended themselves and had to rebuild it, while Wrynn had his kingdom destroyed by the orcs in Warcraft: Orcs and Humans and also had to rebuild it).
Back in Warcraft III, Thrall's story arc seemed to very strongly mirror Arthas'. Thrall starts off as a slave but eventually becomes the warchief and saves the world through his sheer charisma and decision to ally with his people's former enemies. Meanwhile, Arthas has everything going for him in the beginning but his single-mindedness and arrogance lead to his becoming a slave to the Lich King and the death of his people. Unfortunately, this relation doesn't get any spotlight in the game itself.
Wordof God is that Garrosh Hellscream is also foil to Thrall. He replaces him as warchief and is a warlike, hot-headed, eventually evil orc, like the typical stereotype except in intelligent, whereas Thrall is a sensible peacemaker. In the Mists of Pandaria expansion, when Garrosh turns evil, King Varian learns to be less like him by comparison and thus also becomes a bit of a foil to him.
In Tides of War, Garrosh and Jaina are foils. Garrosh is described by author Christie Golden as a weak person with a malleable core, who is molded by his environment. By contrast, Jaina is often wounded by traumatic events, such as the destruction of Theramore, but her "core" remains intact.
Gorath and Owyn from Betrayal at Krondor can be considered this for each other, starting with their appearance - a towering menacing-looking dark elf warrior with greying slate black hair in armour and a cloak, and a very scrawny 19-year-old human boy mage apprentice with fair hair, innocent blue eyes and wearing a light robe in warm, sunny colours. Then there's the personalities - stoic, reserved, guarded and pragmatic vs. bubbly, expressive, emotional and generally trusting and eager like a puppy.
Final Fantasy V has sisters Lenna and Faris. Lenna is polite, diplomatic, astonishingly selfless, and a princess who is associated with the Water element. Faris is coarse, joins the quest mostly for answers about herself, was raised as a pirate (with no compunctions about ransoming princesses) and a man, and is associated with Fire. Lenna is also more mature about accepting death and other life-changing truths while Faris' instinct is denial. As the story progresses, Faris becomes more caring and altruistic like her sister and they love each other, but the differences in their upbringing continue to make them quite different people.
Final Fantasy VI had Kefka and General Leo, the two main generals of The Empire. Kefka was a Bad Boss, whereas Leo was a Worthy Opponent. The two were more or less polar opposites in every way, the latter existing primarily as contrast to the former. Terra and Celes, fellow magitek knights and the main characters of the game, also are foils of Kefka...while Terra and Celes learn the value of human life over the course of the game, Kefka sees human life as more meaningless as the game wears on.
The Arch EnemiesCloud and Sephiroth are opposites or mirror images in just about every way. Even their appearances were apparently designed on this basis. whereas Sephiroth was the absolute elite of SOLDIER apparently even as a teenager, Cloud never made it to their ranks at all. Both angsted at some point that they were the result of a terrible experiment. Sephiroth at first seemed to find out that it wasn't that bad after all, that he was merely built to be the last of the Ancients, but in fact it was if anything even worse than he had thought at first. Cloud seemed to find out that he was nothing but a soulless clone, but actually it was much less severe than that. Where through the course of the game we find out how Sephiroth progressively stops caring about humanity, the Ancients and the Planet Cloud goes from Only in It for the Money to caring about AVALANCHE, the Planet's plight and everyone through the course of the story. For each, the time when they find out the whole truth is when they fully became the hero and villain they are.
To another extent, Aeris and Jenova are also foils in relation to their influence over Cloud and Sephiroth respectively.
Almost the entire game revolves around the head-butting relationship between Squall and Rinoa. But that just makes it all the sweeter as the game progresses and the player witnesses Squall's multiple occasions of emotional 180. Also, THE ENDING SCENES.
Also features the prominent example of Squall versus Seifer. They're both top grade students, specialized in a difficult (and slightly unconventional) to manage weapon, and stand out amongst the crowd going decidedly against the flow. They've also butted heads against each other since forever. However, while Squall appears aloof while being introvertedly struggling with whatever issues that comes to his mind, preferring not to be bothered by other people. Seifer is very much extrovert, enjoying excersizing his status as Head of the Disciplinary Comittee, being very vocal about his goals and ambitions, and clearly likes the leader role of his posse. They can both come off as rude, Squall because he doesn't get other people, Seifer because he likes being rude. As the game progresses, Squall grows closer to his party, while Seifer grows more distant from his posse. As Squall overcomes his past issues, Seifer becomes more obsessed and trapped in his. They both become Sorceress Knights, Seifer to fulfill his childhood romanticiced dream, Squall as a natural step in the chain of events. Also, the stronger and more confident person Squall becomes, the more ragged and dragged down Seifer becomes. They also both had a relationship with Rinoa, Seifer had a brief summer romance, Squall a longer relationship evolving from initial meh, to very real romantic feelings.
The Mega Man (Classic) series has it. The most prominent is Bass and Mega. Going by the coloring of their armors, Mega perfering brighter colors and simplistic design to Bass's Darker and more complex looking armor. The reasons why they fight are different, Mega fights to protect people and asked to become a fighter, where as Bass was created to fight and continues only to prove that he is the strongest.
Proto Man operates as this to both Mega Man and Bass. He's free-willed and independent in contrast to Mega Man. Similar to Bass as he used to be Wily's Dragon. However, he eventually becomes more heroic and allies himself with Mega Man of his own free will unlike Bass who is single-mindedly driven to prove himself the strongest.
On an ideological level, the Mega Man (Classic) series could be seen as a conflict between the ideals of Dr. Light and Dr. Wily. Whereas Dr. Light wants to have a future where robots can benefit mankind and eventually develop their own free will, Dr. Wily only seeks to further his own goals with his robots. This can even be seen in the X series, where Wily created the initial Maverick virus to sow further chaos between robots and humans.
Two examples from The Legend of Zelda: Twilight Princess. The first example is Midna for Zelda. Midna is a Tsundere, whereas Zelda is a Proper Lady. Midna is a Deadpan Snarker, whereas Zelda is far less abrasive in her words. And let's not forget that they're both princesses. This is even reflected in their Leitmotifs, with the melody for Midna's theme being a minor key version of Zelda's. The second example is Zant for Ganondorf. Zant is secretly a Psychopathic Manchild who maintains a calm demeanor up until the very end, whereas Ganondorf is deathly calm inside and out. Zant borrows the power of another being in order to achieve his ends, whereas Ganondorf had gained his power by means of his own resourcefulness and deceit.
Ghirahim is also a foil of Fi. While she is stoic, subdued, reserved, and very technical, Ghirahim is flamboyant, lets all his feelings out, and is a drama queen. Turns out both of them are sword spirits.
In a strange case of a character being the foil for themselves, the Ganondorf in Twilight Princess was specifically designed to contrast his appearance in Wind Waker. In the Wind Waker timeline, Ganondorf is humbled by his defeat at the hands of the Hero of Time and the Goddesses' flooding of Hyrule, leading to an Older and Wiser Ganon who, while still evil, shows signs of being a Noble Demon and Well-Intentioned Extremist who seems to genuinely regret some of his past actions, or at least the way they turned out. In the Twilight Princess timeline, however, Ganondorf's initial plan to get the Triforce is thwarted before it even begins, only for him to later get the Triforce of Power anyway due to a "divine prank" that was the result of the Hero of Time's Time Travel. This turns Ganon into a manipulative, sadistic brute with a god complex and no redeeming qualities whatsoever.
In The Legend of Zelda: A Link Between Worlds, Link has a foil in the form of Ravio. Link is a Heroic Mime whose main character trait is that he's courageous and often willing to help out anyone without expecting a reward. Ravio, while a good guy, is a talkative coward who only appears to care about making a profit. It turns out that Ravio is actually Link's Alternate Self from Lorule, Hyrule's Alternate Universe. It's also revealed that they both deeply care about their respective worlds and their princesses, Zelda and Hilda.
Mipha and Zelda in The Legend of Zelda: Breath of the Wild. Both are princesses with great duty resting on their shoulders, with a strong desire to make their fathers proud. Mipha is Link's childhood friend when Link met Zelda after he became the chosen hero. Where Zelda is tsuntsun towards Link and vocally wished he would stop following her, Mipha is deredere and wanted to be with Link after their duties are over. Mipha strongly implies that she would think about Link in order to tap into her healing power. Zelda would obtain her own power when she protected a badly injured Link from the Guardians.
Each of the four races has both a Champion from the backstory and a modern ally of Link's who each contrast each other in terms of personality and other traits. Revali of the Rito is a boastful and flashy archer who sees the coming battle against Ganon as a chance to show off his skills to the world, while Teba is a terse and stubborn man who just wants to protect his people; both start off dismissive of Link but gradually come to acknowledge his skills. Daruk of the Goron is a boisterous warrior who acts as The Leader of the Champions in the flashbacks, while Yunobo is a young Cowardly Lion who must be guided by Link to incapacitate Vah Rudania. Mipha of the Zora is The Quiet One, very reserved, and uses healing magic, while her brother Sidon is energetic, sociable, encouraging, and is portrayed as relying more on his physical combat prowess than his sister did. Urbosa of the Gerudo is a composed Cool Big Sis for the Champions, while Riju is a young ruler who feels like an Inadequate Inheritor to her mother.
From No More Heroes, Henry to Travis, "Don't look at me. I'm just the cool, handsome foil, who also happens to be your twin brother."
Street Fighter has Ryu and Ken. Ken is a world famous martial artist who is married with a child, while Ryu is currently a wandering warrior who always travels the globe to seek new opponents to fight.
Kain and Raziel. One's a vampire, one's a wraith. One feeds on blood, the other on souls. One wields a sword that feeds on blood, the other wields a wraith-blade version of the same sword that feeds on souls. One has telekinetic powers that allow him to fling people around like ragdolls, the other can just knock people over with them. One transforms into mist and walks through barred doorways, the other shifts into the spectral realm and phases through them. One spends most of the series running a very complex scheme across time and space, the other spends most of the series being manipulated by anyone with half a brain. One of them has a very concrete desire to rule the world, the other swings between wanting revenge, wanting to understand himself, and wanting to save his own life. One's a king, the other used to be his right-hand man... and yet, both of them are messiah-figures.
On the heroes side, we have Chris and Leon. Both men were thrown into the Zombie Apocalypse early in their careers on the police force. As the years went on, both characters developed quite differently from each other. Leon becomes The Snark Knight and will apply it to friend or foe, but he'll always go out of his way to save and protect people that are defenseless against the bioweapons. Chris, however, falls into Knight in Sour Armor and becomes The Cynic, wondering if all this fighting is even worth it at this point. Not only does he becomes even more sour and cynical, he even briefly becomes The Alcoholic to null the pain of the endless fighting and the loss of his squad. Thankfully he does get a bit better.
The World Ends with You's game manual openly states that Neku and Beat are a complete opposites. The former is a Deadpan Snarker who gradually learns to open up to people and fight for the sake of people besides himself, while the latter is especially devoted to his partner and sister to the point where he would join with the Reapers in the hopes of restoring her to normal.
And, depending on how you see it, Beat and Rhyme, too. Beat seems Hot-Blooded and devoted to becoming the best skater ever, while Rhyme is calm, but doesn't have a dream of her own. It eventually turns out that they're the opposite of how they seem at first; Beat initially lacked motivation, while Rhyme "had a million reasons to live", in Beat's words, and she kept believing in him.
Neku and Joshua are also very obvious foils, and it can be argued that this contributes significantly to both of their character developments. Both have very negative outlooks on the world, initially, and have extraordinary trouble understanding other human beings around them. Joshua even goes so far as to constantly point out these similarities between them, egging Neku on about it, until Neku points out that he actually has a desire to understand people and not just give up on understanding them altogether (which comes as a genuine surprise to Joshua.) Also there's the fact that Joshua was responsible for Neku's death and involvement in The Reapers' Game, making him technically an antagonist all along, which makes their similarities equal parts interesting and ironic, and even emphasizes the different viewpoints between the two of them. It's also implied that Neku's change of heart over the course of the game is what spurs on Joshua's change of heart and ends up actually saving the day.
Lots and lots of foils in the Mass Effect series, almost all of them with Shepard. No matter how you play as Shep, the following foils apply:
Shepard and Garrus. They have exactly the same morals, but where Shepard is confident and certain, Garrus is confused and looking for guidance. He's basically the living embodiment of the game's Karma Meter.
Shepard and Saren. Both are charismatic individuals who can convince anyone to follow them. The differences are large when you're Paragon, and almost minimal when you're Renegade. Whereas Saren used trickery, false promises and mind-control to gain the support of the Geth, Krogan and Rachni, Paragon Shepard can earn their loyalty through trust, cooperation and mutual respect.
Shepard and Javik. Both hold the rank of Commander and lead the fight against the Reapers during their respective Cycle, causing them to be revered throughout the Galaxy. However Javik is essentially a more hardened version of Shepard, one who lost his ship, his crew and ultimately his entire race to the War.
Mass Effect: Andromeda introduces "the Builders," the ones who created all the Remnant technology that does anything interesting in the cluster. They are foils to the Reapers. The Builders were benevolent creators who left behind tech that looked sharp and dangerous, while the Reapers were malevolent destroyers who left behind tech that looked soft and useful. The Builders wanted people to understand their technology (but got wiped out before they could finish teaching the angara), while the Reapers didn't want anyone to progress at all except along pre-planned paths.
In Borderlands 2, Handsome Jack has two foils: Torgue Flexington and Professor Nakayama. All three are CEOs or high corporate executives (and in the second case, founder) of their respective corporations, but Torgue and Nakayama are both basically exact opposites of Jack in terms of his different dimensions.
Elson and Cazarosta. Elson is sociable, emotional, and places a high value on honourable conduct in war, Cazarosta is cold, stoic, and believes that in war, expediency comes before honour.
Major Hunter and Captain Lefebvre. Major Hunter is bold, friendly, and effusive, Captain Lefebvre is cold, cautious, and reserved.
In Katawa Shoujo, Hisao points out Shizune and Misha contrast with Lilly and Hanako. Lilly is elegant, refined, calm and popular in the school (although she doesn't let many people close to her), whereas Shizune is brutally honest and driven, which has resulted in her being somewhat unpopular (despite her desire to have friends and make people happy). Misha is cheerful, energetic, but also blind to social cues, while Hanako is meek, timid, and pays careful attention to social cues.
Ahri is a fox who wished to be human, and was granted it by a dying wizard. However, her humanoid form is still somewhat incomplete, so she searches for a way to become fully human without taking lives, if at all possible (since her new human form came with a conscience). Warwick, on the other hand, is a human hunter who wanted to become stronger, so he drank an incomplete potion that turned him into a wolf-man. He revels in his newfound form and greatly enjoys killing people and tearing them into bloody shreds, but due to the incompleteness of the potion, his wolfish form causes him to lose a little more of his humanity every day...
Poppy and Kled are Yordles who are strongly associated with the rival empires of Demacia and Noxus, and embody their most prized virtues through long association. Given what those virtues are, Poppy is a humble soul, a hero who shows up to protect innocents, and a champion whose playstyle is very defensive and team-oriented, while Kled is a feral, drug-addled, selfish, ambiguously cannibalistic murderhobo whose playstyle is pretty much pure vicious aggression.
The God-Generals in Tales of the Abyss are carefully designed to reflect each member of the main party. Fitting for a game that revolves heavily around Cloning Blues.
Luke and Asch are clones of each other. One wears white, one wears black. Luke is eventually repentant, deeply bonded with his companions, forgiving, and accepting of his identity. Asch is aggressive, unapologetic, solitary and believes his identity has been destroyed.
Legretta and Tear are both staunchly loyal fighters doing what they believe is right. Both are love interests to major male characters, but Legretta is bitter because her love is dictated by the Score, and Tear honestly falls for someone who isn't even supposed to exist.
Anise and Arietta are both Fon Master Guardians. Both are also having a bit of family trouble: Arietta's mother is the liger you kill in the first hour or so of the game, and Anise's parents are basically being held captive by Mohs. They both have a single goal that drives them - Arietta wants the Fon Master back and Anise wants a rich husband. Arietta doesn't get over her desire, and Anise does. Also, Arietta is openly sad most of the time and Anise is deceptively cheery.
Jade and Dist are both scientists credited with developing fomicry and they're both showboats in their own way. However, Jade keeps his emotions in check while Dist is wildly expressive, and Jade recognizes the flawed and morally ambiguous nature of their creations while Dist wants to continue studying them.
Natalia and Largo are both honourable and duty-driven, and they both get Heroic BSoD 'd upon losing their love interests. Natalia manages to stay optimistic while Largo crosses the Despair Event Horizon pre-game.
It would seem that Sync and Guy are designed to be foils based on their speedy fighting style, but when it's revealed that Sync is another replica of Ion, he becomes the foil for the Fon Master. Both see their lives as worthless, but this realization makes Ion dangerously passive and Sync destructively aggressive. As a survivor of the Hod War who hopes to take revenge, Guy's foil is actually probably Van, considering how Guy manages to get over his feelings (mostly) while Van doesn't.
Zelos and Colette are both The Chosen One, but while Colette is wholeheartedly dedicated to her role, Zelos is a hedonistic playboy who couldn't care less. Both of them also see their own lives as expendable, but for different reasons. They can also both give Lloyd gifts that will protect him on the final run to the Tower of Salvation, and both can snap Lloyd out of his Heroic BSoD when he finds out Kratos is his father.
Zelos also serves as a foil and Suspiciously Similar Substitute to Kratos - they fight in the same style, they both have red hair, etc. They have both given up on escaping the corrupt Cruxius system until they meet Lloyd, and they both appear to betray him for exactly that reason. This is a bizarre case in that their roles are the same, but their personalities are entirely reversed.
Milla and Gaius. Both are fiercely loyal to their respective missions, ranging into Blood Knight territory to achieve it. But while Milla slowly begins to warm up a bit, Gaius remains on the path of his mission and gets close to becoming what he hates. Jude even lampshades that Gaius' words about his intentions sounds similar to Milla's about hers.
Milla and her sister Muzét. Milla is a very independent person and believes in following one's own will. On the other hand, Muzét is very lonely and severely dependent on someone, becoming dangerously psychotic when she doesn't have someone. When the real Maxwell drops her by stating she's just a tool, this was one of the reasons why she willingly gave her strength to Gaius. There's even a skit where Milla mentions that Muzét is her 'dark shadow'.
Solid Snake and Raiden in Metal Gear. Snake is older and grizzled, Raiden is young and inexperienced. Snake is cynical, Raiden is idealistic. Snake is Tall, Dark, and Handsome, Raiden is a Pretty Boy with white hair. Snake... has a healthy libido, Raiden has a steady relationship. Snake is a modern stealth operative, Raiden is a more traditional ninja. Snake likes guns, Raiden prefers blades. Total opposites.
Dr. Vahlen and Dr. Shen of XCOM: Enemy Unknown. They're both scientists, but they both take opposite approaches to it. The young, spirited Vahlen is analytical and idealistic but destructive; while she acknowledges that science can be used badly, it's progress must be unhindered, and in the end, it will work itself out. The older, wiser Shen is creative and constructive but cynical; he believes that scientific progress must be slow, and he's very cautious about the moral implications of his work. It is left up to the player to decide which attitude is correct.
The coarse Sheriff Bigby is overseen by Snow White, a strait-laced, immaculately clad bureaucrat. This is mirrored in their past selves: a savage wolf and a beautiful princess.
Snow is also contrasted with Ichabod Crane: he's an authoritarian jerk who's embezzling money from Fabletown citizens, she's a compassionate mediator who honestly believes in the law's power to help people.
The Followers of The Apocalypse and The Brotherhood of Steel are both organizations looking to gather lost knowledge and technology from the old world, in an effort to help humanity, but otherwise couldn't be more different: The Followers are very inclusive to others, unprejudiced, non-violent (to a fault), and are trying to help others through humanitarianism; trying to provide other with clean water and food, offering medical aid, teaching others how to care for themselves etc. The Brotherhood on the other hand (with the exception of Elder Lyons and his followers), are reluctant to work with outsiders at best, opening xenophobic at worst, are very prejudice against mutants, very militant, and generally only "protect" people from themselves, by hoarding advanced weapons and technologies, that they feel humanity is too irresponsible to use safely... unless you're one of them, than it's okay to use high-tech weapons.
Similarly, Fallout 4 has this for all the major factions:
The Minutemen combine the parallels in their early history to the NCR (both started out as a bunch of tiny settlements sticking together for mutual survival and prosperity) with invoking a virtuous and romantic memory of pre-war America, as opposed to the Enclave with their twisted vision of a re-emergent United States built on the genocide of most of the mutated Wastelander population.
The Institute has a lot in common with both Mr. House and Caesar's Legion. Like House, they built a technocratic, highly-advanced and secretive oasis in a wasteland, but House used his scientific genius to find commercial success, while the Institute are purely science-centered. House was also motivated by a wish to preserve what little exists of the pre-war world, while the Institute wants to completely destroy all traces of pre-war America and existing emergent cultures throughout the Commonwealth and replace it with their own, very much like Caesar's Legion. The Irony of course is that Caesar's Legion are textbook Evil Luddites and the Institute would probably be revolted by them.
The Railroad tend to have a lot in common with the Followers of the Apocalypse with their humanitarian ideals, but place far more emphasis on anarchism, while the Followers actively tried to distance themselves away from this stereotype. Basically, the Followers are Neutral Good, and the Railroad are Chaotic Neutral. The Railroad also contrasts with the Brotherhood of Steel, as the former treat Synths as oppressed people while the Brotherhood don't see any humanity in them and wish only to exterminate them, and the Railroad are covert while the Brotherhood are fond of big, loud entrances.
Kellogg, the Disc-One Final Boss, is something of an Evil Counterpart to Sole Survivor. Both of them had a loving family that was taken from them (in Kellogg's case, his family was killed by raiders; while the Survivor's spouse was shot and son was kidnapped by Kellogg), but whereas Kellogg coped by becoming a ruthless gun-for-hire, the Survivor went on to become a force of good in the Commonwealth (though the degree of "good" varies depending on which faction they side with).
Among companions, X6-88 is this to Curie and Nick Valentine. Nick Valentine is a badly degraded Gen. 1 Synth and is obviously a machine from a glance, but is a kind soul because his personality was based on that of a pre-war police officer. Curie is a Miss Nanny robot who nonetheless is sentient and sincerely wants to be seen as a person. X6-88, however, remains a thoroughly heartless and cold machine in spite the Institute's efforts to make him and his Courser ilk flawlessly human on the outside.
Preston Garvey is a Minuteman who stands out for being relatively normal and straightforward, with a professional soldier's personality. Deacon is an enigmatic Railroad agent who speaks with a breezy tone and uses a lot of lingo.
Strong and Cait are both bloodthirsty savages who revel in violence. The big point of divergence between them is Strong's belief that strength comes from sharing, which leads him to altruism and being interested in humans. Cait, on the other hand, is self-centered and cynical, having little interest in helping anyone except herself.
Preston Garvey and the Nuka-World companion Porter Gage: Preston Garvey represents everything good about those living in the wastes as a Minuteman, while Gage represents everything evil about people as a hardcore Raider.
Throughout the series, Edgeworth and Gumshoe are paired with one another in ways that suggest a strong foil dynamic, especially in the Investigations games. Though Gumshoe is relatively flat compared to Edgeworth, the two maintain their "opposites attract" (though not in a romantic way) dynamic throughout the Ace Attorney series via Edgeworth's firm, commanding, capable presence and Gumshoe's lighthearted, bumbling assistance. This is especially true in Ace Attorney Investigations: Miles Edgeworth, where their trusting relationship is juxtaposed with a series of relationships which fall apart due to a lack of trust.
The Trials and Tribulations character Iris shares one pivotal trait with Phoenix: they will both do anything to protect their loved ones. However, Phoenix is emblematic of everything good about that trait, and Iris learns firsthand how much suffering it can cause. Several people die because Iris directs unconditional love and loyalty towards her sister, who has done nothing to deserve it. This is why Iris doesn't resent the court for sending her to prison.
Ace, an unrepentant murderer who uses his prosopagnosia to justify his crimes, is contrasted with Snake, a blind man who is self-reliant, proud of it, and genuinely heroic. The two literally fight at one point.
VLR contrasts Akane Kurashiki with Tenmyouji. She's a compassionate yet distant esper whose plans are global in scope and involve sacrificing the few for the many; he's an humanist normal man who despises Akane's micromanaging and contents himself with caring for one person (his son, Quark). This is one reason why players are often surprised that they used to be lovers. Used being the operative word here.
Wealthy, elegant Yumi's idealism is contrasted with jumpsuit-clad Yomi's pragmatism and destitute childhood.
In the Rising Tide expansion for Civilization: Beyond Earth, the newly introduced hybrid affinities each act as this to one of the base affinities present in the original. Purity/Harmony uses biology to optimize humanity while pure Supremacy uses robotics to optimize humanity. Supremacy/Purity pushes forward a philosophy where humans use machines and ingenuity to tame and overcome nature, which clashes with Harmony's use of biotech and genetic modification to better harmonize with the alien environment. Harmony/Supermacy presents an unfamiliar mish-mash of alien biology and cybernetics which would horrify an advocate of Purity, who would put preservation of human form and identity first.
Little Busters! has Rin and Sasami. Sasami's a Girly Girl with a Tomboy Streak who is usually seen with her Girl Posse. Rin is a Tomboy with a Girly Streak whose only friends were the male members of the Little Busters before Riki started recruiting other girls to join. Rin is a Kindhearted Cat Lover, while Sasami prefers dogs. Both are very popular among the male students, but react differently. Rin is oblivious to their feelings because she doesn't understand the concept of love, whereas Sasami doesn't care if a guy is interested because her focus is on Kengo. Sasami is a member of the girls' baseball team and an ace hitter, whereas Rin is an ace pitcher for the Little Busters who only took an interest in baseball because of her brother Kyousuke's sudden interest in the sport. Their routes are even foils to one another. Rin's route involves her transferring to a new school and eventually running away with Riki, whereas Sasami's route involves her remaining confined to Riki's room because she'll transform into a cat if she goes outside.
The dual protagonists of the game, Alm and Celica. While both are fundamentally kind, and begin as naive to the world due to their sheltered upbringings, Alm is the more militant of the two, eager to drive the invading forces of Rigel out of their homeland Zofia through battle, while Celica seeks peaceful negotiations with them. Their disagreement ends up driving a rift between the two during the course of the game. Alm as he's portrayed in Fire Emblem Awakening is even morseo, as his Adaptation Personality Change turns him into something of a Blood Knight, and in dialogue he notes that Celica tells him that he should be more compassionate.
The remake of Gaiden, called Shadows of Valentia, turns Gray and Tobin, two villagers from Ram and Alm and Celica's close friends, into this. Gray is carefree, laid back, witty and fairly street savvy, while Tobin is excitable, cautious, somewhat socially oblivious, and prone to insecurity. They're Those Two Guys over the course of the game, though, and remain close friends.
Luke and Roderick, two members of Altea's 7th Platoon. Luke is the somewhat dim-witted, excitable go-getter, while Roderick is calm, much more serious, and focused. They're close friends and partners regardless.
Two of the three protagonists, Eliwood and Hector. Eliwood is somewhat frail and slightly built, well-spoken, thoughtful and polite, while Hector is very physically imposing, blunt to the point of being somewhat rude, and tends toward recklessness. The two are Heterosexual Life-Partners regardless, and support one another over the course of the game.
Dagoth Ur, the deranged Physical GodBig Bad of Morrowind, is one to the Underking, a key player in the main quest events of the previous game in the series, Daggerfall. They both died originally and became what they are now after being betrayed by someone they trusted. However, while Dagoth Ur wants the Tools of Kagrenac so that he can complete Akulahkan and use it to declare war on his enemies and secure his rule forever, the Underking wants the Mantella to prevent anyone else from using the Numidium for war and so that he can finally die. Also, the Hero of Daggerfall is able to join the Underking, while the Nerevarine is unable to join Dagoth-Ur.
Ragna the Bloodedge and Ruby Rose are both red-and-black-clad protagonists who come from fantasy-esque settings and fight with transforming scythes, but Ragna is cynical and unfriendly while Ruby is kind and optimistic. Ragna is also an older brother while Ruby is a younger sister.
Ragna actually has a lot more in common with Ruby's sister Yang. Both of them grew up in isolated homes in the woods, have blonde hair (or Ragna had before his turned white), both have powerful abilities that involve their eyes turning red, and they're both older siblings with a selfless and protective attitude. They also both rarely open up to others and there's more going on under the surface than they'd like others to see: Yang puts on a warm and friendly smile to deflect away from her inner turmoil, and Ragna acts rude and hostile so others will stay away from him.
By the same token, secondary protagonists Jin Kisaragi and Weiss Schnee are both characters with powers over ice and Jerkass tendencies who act as contrasting rivals to the main character of their respective works. The difference is, Weiss gradually developed a healthy respect for Ruby and came to befriend her, but Jin still despised Ragna and even after Jin performed a HeelFace Turn, their co-operation is strictly an Enemy Mine.
Blake Belladonna (RWBY) is a mirror of Makoto Nanaya (BlazBlue). Both girls are a Little Bit Beastly (Blake is a cat girl, Makoto is a squirrel girl) and their early lives were dominated by Fantastic Racism and how they coped with it defines who they are now; Makoto quickly made human friends and embraced her non-human heritage in a healthy way, but Blake more cynically hides her cat ears from everyone - her own teammates only found out because she slipped up in an argument with Weiss. In personality terms, Blake's intelligent introvert couldn't be more different to Makoto's airheaded Nice Girl. Interestingly enough, Makoto is also actually Not So Different to Weiss: they both had troubled upbringings and went to military school to get away from it all; Weiss is a perfectionist who fights skilfully with quasi-magical abilities while Makoto uses brute strength and generally prefers to just wing it.
In Star Wars: The Old Republic, the early Korriban sections of both Sith classes feature a rival character who is a foil to the opposite Sith class: the Sith Inquisitor's rival, Ffon Althe, is, like the Sith Warrior, the proud scion of a powerful Sith bloodline and is being given special treatment by the overseer training them—but unlike the Warrior, Ffon doesn't have any ability to back up his boasting and when faced with a challenge he can't overcome, he just gives up while the Sith Warrior verges on being an Implacable Man who doesn't let anything stop them from accomplishing their goals. He also turns out to be a massive coward, quickly cracking under pressure when questioned about his failure by Darth Zash and gets killed for it; meanwhile, when similarly grilled by Darth Baras, the Warrior keeps their cool and is allowed to live. The Warrior's rival is Vemrin who, like the Inquisitor, comes from a lower status (the Inquisitor is a former slave; Vemrin is mixed blood) and fought hard to get to their current positions—however, Vemrin lacks the Inquisitor's cunning and is unable to outthink his opponents. In the end, it causes him to try and ambush the Warrior during the final trials, despite the latter being clearly stronger than him.
Clementine and Sarah in The Walking Dead are children that are similar to each other and yet are quite different. Clementine was taught by Lee on how to use a gun to defend herself and how to be resourceful when the going gets tough. Sarah, on the other hand, is completely sheltered by her father, whom she relies on to protect her. Unlike Clementine, Sarah does not know how to defend herself or how to do anything else and the moment things start to turn bad, she'll either freeze up, panic, or completely lose it. Sarah is also a few years older than Clementine, yet acts almost younger than her due to a possible disorder and her being sheltered by her father.
Rean and Alisa in The Legend of Heroes: Trails of Cold Steel are foils to one another as both do meddle in the affairs of their own classmates, both are truly neither commoner nor noble (Rean is an adopted noble while Alisa's too rich but is still technically a commoner), and both are studying at Thors though Rean wants to find his place in the world while Alisa wants to gain independence from her family. Rean is more rational and calm while Alisa is more hotheaded and Rean uses a sword while Alisa uses a bow. Finally, Rean's primary and secondary elements (Time and Fire) contrast Alisa's two elements (Fire and Space).
Rosé and Seiji have a fair few traits in common, and even their differences tend to mirror each other, which is made clear by Rosé replacing Seiji as one of Akira's companions: both are good-looking, polite, dexterous people who hide a darker side, have criminal ties, know unscrupulous skills like picking locks, and have little problem with going against the law. Whereas Seiji is a young man who likes older women, Rosé is an older woman who likes cute young men, and while Seiji is terrified of the supernatural, Rosé is an expert on it.
Ooe is revealed to be one for the Killer Peach. Both are (or were, in Peach's case) women of the law who prioritized the exposure of injustices over following the rules. They both also lost their families thanks to the employees of Sumii Co. It's this connection between them that causes Ooe to act rashly towards Killer Peach. Later on, she admits that she understands the Peach's murderous rage, but that her methods are wrong and Ooe wants to do right for her by pursuing justice within the realm of the law (somewhat, at least).
Ciel nosurge and its sequel, Ar nosurge: Ode to an Unborn Star, has Ionasal.kkll.Preciel, one of the main protagonists, and Zillillium Rimonite, one of the main antagonists. Both characters desire peace among humans and Genom, and fight to protect the Genom and planet Ra Ciela. However, Ion is a heroic, optomistic idealist who believes there is good in everyone, while Zill sees humans as selfish beings and believes the only way to peace is an Assimilation Plot. They even have inverted clothing colors: Ion wears a lot of white and sometimes blue while Zill is more partial to red and black.
Yakuza Series protagonist Kazuma Kiryu and his best frenemy Goro Majima are foils to each other. Kiryu is a Hot-BloodedEmotional Bruiser, who hides a rolling sea of powerful emotion beneath a façade of grim stoicism. Majima is a calm, intelligent and introspective man who hides his true self beneath a mask of Joker-like Ax-Crazy nuttiness. Kiryu generally eschews weapons, preferring to fight with his fists. Majima's signature weapon is a tanto, but he also likes baseball bats, and will fight with whatever he can get his hands on. Kiryu is a bear of a man whose fighting styles are mostly built around power, Majima is lithe, almost cat-like, and favors mobility and speed. Kiryu is most comfortable punching his problems, Majima is business-savvy and has run several legitimate businesses on the side of sitting in the upper echelons of the Tojo clan. Kiryu was ultimately forced out of the yakuza to protect the people he loved, in spite of not really wanting to leave, while Majima, who would probably have been happier as a civilian, was drawn deeper into the world of crime for his loved ones.
Rie and Runa. Apart from being the Tomboy and Girly Girl duo, Rie is casual, playful and from a wealthy family, while Runa is polite, mature and poor. Rie tries to win over Taiko, while Runa had once been in love with Hiro, but had gotten over it (although she still doesn't realize what kind of person he is).
Rie and Taiko. The former is the kind of person who would believe in her friends even if the facts are against her, while the latter has a strong sense of justice, and is willing to suspect his friends to find the truth. Ironically, Rie's belief in Runa's innocence is entirely justified, while Taiko's anger over what happened to Kotoba causes him to become irrational.
Monster Prom: Zoe and Leonard are this to each other. Both are huge geeks deeply devoted to fandoms. Zoe however, represents the positive sides of fandoms, like her openness to new things, how she dedicates herself to have fun with the source material and how she applies her own creativity to create more content based on sources she likes. Leonard, meanwhile, represents the negative sides of a fandom, he's overly critical and nitpicky, cynical, entitled and is constantly complaining about not being catered to.