You probably know all about this - since so many video games come from Japan, of course a lot of Tsundere archetypes are present. There are just as many Tsundere characters in Western games, though! Just read, already!
Leon. Although in the original game, he was a complete jerk who never accepted his former companions as friends, the Remake rectified his personality. Although initially mistrusting and openly stating that he dislikes Stahn Aileron, he eventually caves into his persistent attempts to befriend him and agrees to fight alongside him as a companion. Of course, he then makes a Heroic Sacrifice moments after agreeing to accompany The Hero once more, and he STILL states that he dislikes him, and that he never accepted that he was a friend. Doesn't help that he looks... rather girly despite his masculine voice and fights like a Lady of War.
Rutee. (Wow, she and Leon must've been real Tsundere siblings), who continually bickers with Stahn, but still ends up as his wife in the sequel. And in the said sequel, there's Nanaly Fletch, who constantly delivers Loni a backbone crusher if he pisses her off, especially about her tomboy nature, but in another second, she gets... a bit gushy on him. She even cried on his shoulder once.
Rita Mordio. Although in this case, her deredere side comes out with Estelle.
Nan, who acts this way towards Karol. She reveals this most when she fights him as the last fight for his version of the 100-Man Melee, when she even explicitly says that she's fighting him because she can't have the guy she marries be weak. Followed by him wondering why she's attacking him then, further triggering her tsun side. In fairness to Karol, he's about ten years old.
Tales of Hearts presents another subversion to the "Hero x Tsundere" pattern. While it initially looks like love interest Kohak is going to be a tsundere, she's pretty mild, and Token Mini-Moe Beryl Benito soon turns out to be a much more advanced case, nursing a crush on Shing for about 70% of the game. And on the distaff side, Hisui can be found struggling this way over his burgeoning 'ship with Richea.
There's also a mild, subverted case in Tales of Rebirth, but not about The Hero, though. Annie Barrsreally hates Eugene Gallardo, but she always does help him. When asked why, she usually replies like "I-it's not that I have forgiven him..." Unlike other Tsunderes, though, Annie is not very violent with the other members, and after she forgives Eugene, she stops being a Tsundere, and their relationship were strictly non-romantic.
Hubert's pretty much a jerk for all of Tales of Graces, but Asbel and especially Pascal can bring out a sweeter side in him. This is most obvious during all the Ship Tease in Lineage and Legacies, and in a skit after his optional Duel Boss encounter in the main game, in which he pretty much says "It's not like I lost on purpose so you'd feel better about yourself or anything...idiot."
Bastila from Knights of the Old Republic is cold, rude, and contemptuous of the player for the first half of the game. She does warm up, gradually, only to freeze solid again as soon as she realizes what is happening.
Nathyrra from Neverwinter Nights Hordes of the Underdark is a milder example, being almost friendly (if a bit distant and businesslike) when you first meet her, though things don't really move along until certain events crack her shell.
Morrigan from Dragon Age: Origins fits this profile rather well, initially presenting a cold, at times almost evil disinterest in people and mocking the main character's acts of kindness or affection, believing such feelings are a weakness. If the character continues to pursue her, however, she gradually warms up to him, becoming at times genuinely affectionate, only to suddenly panic at her unfamiliar feelings of attachment and dependency, and immediately try to push him away.
Velanna, the human-hating Dalish Elf of "Awakening" is essentially Morrigan, only much more hostile and spiteful. However she seems to expose a more flustered side occasionally when Nathaniel Howe compliments or teases her. If you defend her to one of her former clanmates, she tells you not to make a fuss over her - but her approval jumps up.
Silk Fox in Jade Empire is rather rude and contemptuous with regard to the player during their initial encounters (during their first encounter, she tries to kill him/her due to mistaking him/her for a mook); but her dialogue during the culminating romance scene is literally "come over here and kiss me before I remember who I am supposed to be." (That particular line was actually there because of Silk Fox actually being Rebellious Princess Sun Lian, but given her earlier dialogue it has a double meaning)
Jack in Mass Effect 2 is one of the biggest Sociopathic Heroines you can recruit and is spoken of fearfully by the prison warden you pick her up from. However if Shepard chooses to help her deal with her past and Male Shepard convinces her that he's not interested in merely sex, she reveals that she hides a deeply vulnerable side that's been wounded one too many times and a need for closure.
In Mass Effect 3, Tali will act this way towards Garrus (provided you didn't romance either one), poking fun at him and telling him that she's just using him for his body. Garrus seems to like it.
Aveline in Dragon Age II can come off as rather cold and harsh to some of the Party Members, especially Hawke and Isabela. The real kicker is that she isn't a love interest.
Any of the rivalry romances in Dragon Age II can actually be seen as this. (Although with Merrill it's perhaps more of a type 2, due to her only tsun moments being related to rivalryHawke's disapproval of blood magic/the mirror.
Midna even falls victim to the classic Tsundere line; "Don't think for a second that I care about you, I'm helping you because I have to" or something to that effect.
Also from Twilight Princess is Plumm, the bird in charge of the Kargaroc Balloon Game at Zora's River/Lake Hylia. When you beat the high score and win the Piece Of Heart, she delivers the classic Tsundere line, "I'm not giving you this because I like you or anything..."
Tetra from The Wind Waker qualifies too. She even gives a Tsundere-line, pretty simmilar to the one Midna gave, early in the game.
Tatl from Majora's Mask probably started the trend of Link having a Tsundere-girl for a friend and helper. She gives the "I don't care about you, but I have to help you" line, just like Tetra and Midna.
Surprisingly, Spirit Zelda is a "sweet but harsh" example, rather than this kind, like the other Zelda-characters listed here.
Lili from Psychonauts. She spends roughly the first half of the game belittling Raz in various ways, but is much sweeter to him in the second half—she's still feisty, though. To be fair, though, she isten. Cooties might have something to do with it.
Tiltyu the thunder mage, from the fourth game. Sure, she acts really cheerful, pushy, spunky, rebellious, and even speaks too casuallyfor a Princess, especially when her predestined is the rather timid Azel, she looks just about ready to be really pushy on him. But in truth, beneath that, she shows great insecurity and loneliness, when you do actually get her to a love-improving conversation with Azel, you get to see that despite her outlook, she is really scared that nobody will trust her by being 'an enemy's daughter'. Then you see how scared she is when facing her father Leptor (justified, though, her father has a Holy Weapon that can possibly kill her in one hit). And then there's all those misfortunes she suffered right after.
The more straight out Tsundere in the fourth game would be Princess Ayra of Isaac. Sure, she can be one hell of a scary Action Girl, killing men with ease using the Ryuuseiken and being a sort of Auntie Bear to little Shanan. But then, she can get a bit gushy when she's paired with Holyn... or have a Slap-Slap-Kiss romance with Lex. If you really want gushy, though, try pairing her with Arden...
For bonus points, Ayra's name can be romanized as Ira. Which is latin for one of the 7 deadly sins... guess which one.
And Ayra's such a tsundere that there's tsuntsun to spare for both her daughter Lakche and Lakche's replacement/expy Radney.
Farina, the tomboyish and money-grubbing Pegasus Knight, is also this kind of Tsundere since she's got the Slap-Slap-Kiss with two males, Hector and Dart the Pirate. Her deredere side shows when interacting with Kent or her sisters Florina and Farina, as well as when she offers Dorcas a large sum of money after hearing about his Ill Girl wife.
Path of Radiance set this up as well in the Cat Girl Lethe and her various interactions with people (especially Ike, the leading male of this story). A lot more with the violent aspects than the nice aspects (to show how feral and feline she is). However, the sequel Radiant Dawn shattered all thoughts of her ending up with anyone.
Must be genetic. this list for the overly generic support conversations in the tenth game suggests that Lethe's twin sister Lyre is the same way (specifically, the level A conversations). She's deredere towards Captain Ranulf, tsuntsun towards pretty much everyone else.
Severa...good god, Severa. The result of being the daughter of Cordelia, a Broken Ace of a woman with self-esteem issues and an unrequited crush on Chrom that she never really gets over made Severa angry and snobbish at everyone; she also likes to spoil herself and is outspoken. In fact, when she first meets Cordelia, she calls her out on her devotion to Chrom. The "dere" side of her is seldom seen, usually being reserved for her S Supports (especially if she's paired with Inigo, Laurent, or the Avatar), and it's implied that despite all of her frustration, she truly loves her mother.
Sue Sakamoto from Cave Story is a Distressed Damsel, but she'll bluster and threaten right up until she's captured (and after!), then yell at you for saving her. She warms up to you as time goes by, though, probably since you end up saving her no less than three times.
Elena from II is also a Tsundere, if not an even more classic case. She constantly yells and gets angry at Ryudo (normally for his sarcastic comments), but has those few moments where she blushes and feels dere dere towards him. She's also much more reluctant than Millenia to admitting her feelings for him.
Cute Monster Girl Annah from Planescape: Torment is classic form of this, primarily demonstrated in verbal jibes and threats, though not so much physical toward the Nameless One (who, in the beginning of the game only has levels in badass, and it shows,) but she's less shy about slapping Morte around. Her dere side doesn't even reveal itself when the man she'd known as her father is found dead, but eventually emerges in some steamy flirtations with Nameless, which become completely realized by the end of the game.
Bishop of Neverwinter Nights 2 is an extreme case of Tsun-Tsun, if your character is female. He frequently makes snide remarks to her, flat-out calling her a whore at one point, and tells her that she'll never know him and that he doesn't want her to know him...right before doing things like turning around and asking her to run away with him or giving her advice on how to beat Lorne. Though it's not as if hecareswhether she lives or dies.
Shandra's a milder version. She'll show signs of being concerned about you during your duel with Lorne, but if you ask her about it, she utters the TsundereCatchphrase: "N-no! It wasn't like I was worried about you...I just wanted to see justice done, that's all!"
Cloche Leythe Pastalia, in Ar tonelico 2, is actively described as this by one of her rival's attacks, ending in a rant about being honest.
Finnel, in the sequel, is described as a 'typical tsundere' by her in-game character profile. It's actually played with a bit though. Her deeper Cosmopheres reveal she's an aversion of All Women Are Doms All Men Are Subs, and acts uppity in the hope Aoto might get fed up and exert some authority over her.
Juere, the Goddess of Healing, doesn't want to heal you at all! S-Stupid! (That's a somewhat modified quote from the game.) She occasionally passive-aggressively begs for you to not stop worshiping her, and the various NPCs comment on her weird tsundereness.
Clevia of Ys VI is practically a demonstration of how to go from harsh-but-sweet to sweet-but-harsh over the course of the game.
From the same game, Hidetoshi Odagiri could arguably be considered a much milder form of this. He's stern and cold to just about everyone in the first eight ranks of his S. Link, even insulting them for disagreeing with him. However, (assuming you gain his trust by agreeing with him at least up to Rank 7) he is very much deredere to the protagonist as early as Rank 2, even going out of his way to clarify things he says just to make sure you don't feel insulted. Heck, he even blushes when praising you for your sincerity and ability to be gentle to people at some point during his last couple of ranks. And on the female protagonist path, he reveals in the end that he has romantic feelings for you.Definitely an example of a Tsundere, albeit a rare male one.
Airi Ban from Devil Survivor 2. Initially, Dumb Muscle Jungo is the preferred target of her wrath, as she thinks he's mocking her even if Jungo is nothing but a perfect gentleman. Later, other targets are Hinako, who Airi somewhat hates for a variety of reasons (Nagoya-Osaka rivalry, breast size, clashing sensibilities) and to a degree Daichi. Gently easing out of this persona allows the Protagonist to coax her softer side out.
Banjo-Kazooie's Kazooie definitely fits. It's easier to miss, though, because there's no switching; the caustic tsuntsun and the sentimental deredere exist in harmony in a sort of yin-yang effect.
Silver from the Pokémon games has Type-A tsundere tendencies, which are given a boost in the recent Gold and Silver version remakes. He is extremely tsun towards the player character and is the first and only Pokémon rival to actually attack the player physically, kicking/punching/shoving him or her even upon their first meeting; and he is constantly called out on how harshly he treats his Pokemon. He does soften up a little towards the end of the game and starts treating his Pokemon kindly, though he still remains tsun-tsun towards the player, and is convinced that he or she is laughing at him.
Liese from Eiyuu X Maou is an inversion; while harsh is her default mode, her tsun side comes out more frequently with everyone but her Love Interest, who she's loyally dere to (The Helper, on an occasion The Nurse.) The Taunt is typical among her True Companions, she rains sadistic torment on all humans, and the rare tsun expression to Felser is reserved and rather chilly. Depending on game choices, she may give him the full Tsunami wrath, but in the end will follow that with dere more extreme than before.
In Radiata Stories, Ridley is tsun tsun to everyone from her arranged finance to her commanding officer and stays that way. As the story progresses her dere dere sides emerges more and more around 'her Jack'. Lily, Morgan and Urusla count too.
Jin Kisaragi from BlazBlue is a rare male example. He has all the qualities of a complete Tsundereexcept when he is around Tsubaki or Ragna.
Ragna, especially towards Noel and Rachel. Much of his dialogue is spent insulting them both, but he's also willing to blow off his own arm to save Noel.
Possibly, Hakumen. Especially in his alternate story mode route in Calamity Trigger.
Hakumen is one most definitely. Remember he's an alternate version of Jin who realizes just how much of a prick he was in the past. Also as side materials will explain that he still has a soft spot for Ragna, and even though his personal obligation to make sure the Black Beast never returns, its still emotionally devastating for him every time he kills Ragna. And that's not even covering his reaction to his encounter with Tsubaki in Continuum Shift.
Even Noel has Type B traits. Just play a match between her and Ragna and listen to the chorus of insults. "I'm tired of being called stupid...BY A MORON LIKE YOU!"
Yukariko only really puts up with the player character's antics and blunders because she doesn't want Suho, Asagi, and Kohaku staying in possession of her body. This being one of Illusion's games, it doesn't take much imagination to see what the "antics" are.
Hiroki in Canvas 2 is constantly described as a 'contrarian.' On the heroine side of things, Tomoki really tries but is too easily distracted to keep it up.
Lucia is a textbook example, being rather cranky and obstinate to everyone, but softening up towards love interest Alph as the story goes on.
The third game in its role-playing offshoot Rune Factory 3 has Raven in this mold.
Gwen from Guild Wars is very tsun until her love interest finally hits her deredere side.
Maida Buckner in Fallout 2. She gets a crush on Sulik while he's stuck working off his debt at her family business; Sulik dubs her "Maida-with-no-smiles." Once the Chosen One gets him out of his debt, she fiercely denies missing him - through sobs.
Meilin from Terranigma torments Ark in many ways. We later see that it's because Ark rejects (or fails to recognize) her love.
In the second game of the Sonny series, Felicity is definitely this way: Her early interactions involve arguing with and trying to kill Sonny and Veradux (to get at a cassette tape Sonny was given by Louis early in the first game), but by the fifth zone she joins your party (claiming that she's only doing it to take out the mayor), and in the final cinematic of the main story she's more calmly explaining to Sonny and the party why she was after the tape in a little more detail. Also, before joining the party she would usually greet Veradux with a throwing knife thrown into his face.
Luciano from Princess Debut is gruff and brushes you off for a while, but with some work you can get his dere dere side to come out.
Starling/Sheryl from the "Cross Brigade"/"Silent Crusade" questline in MapleStory is like this towards the (male) player character, completely with classic tsundere 'It's not because I like you or anything' when she actully does something nice.
Ironically, Asura from Asura's Wrath was like this before being betrayed. he is angry and ruthless on the battlefield, and against everyone else, and dere when around his wife durga and daughter mithra.
GLaDOS in Portal 2. Intitially a straight-up Yandere, when the memories of her former life as Caroline begin to emerge, she softens towards Chell, even going so far as to serenade Chell with a heartfelt goodbye while letting her leave. Portal 2's credit song is pretty much Tsundere: The Song.
Goodbye my only friend...Oh, did I think I meant you? That would be funny, if it weren't so sad.
When I delete you maybe [REDACTED]. ("[REDACTED]" in the on-screen lyrics, but clearly audible as "I'll stop feeling so bad.")
Since the Neptunia series are an Affectionate Parody of games and anime alike, it's a given that there'd be at least one character depicting this tsundere stereotype. The same characteristics are seen in IF, Noire, and Uni. In fact, the tsundere within the latter two gets painfully obvious, especially with Uni when she talks to Nepgear.
Grand Theft Auto: San Andreas: Can Catalina's acting be classed as tsundere...or should she rather be put under Total Nutcase?
There are two prominent tsunderes in Duel Savior Destiny. Lily definitely this kind, and quite aggressive, while the medic Berio... is also like this, but more understandably so and less extreme, putting her on the borderline for the categories.
Caris:(after punching Ryle into the ceiling) "Huh? I woke you up and that's all you can say? Do you want me to give you a submission hold?"
Grace Nakimura of the Gabriel Knight series is abrasive, sarcastic, and generally looks down on her womanizing employer, but she's also very concerned f[or him and genuinely loves him; the dream dragon who oversees Gabriel's Schattenjäger initiation certainly knows it when he cites that three women have loved Gabriel purely (the others being his grandmother and Malia Gedde).
Angelus from Drakengard. She hates all humans, and insults Caim and his party without a second thought. (She could be described as 'the taunter' from the Analysis page.) She eventually changes her views towards Caim and only Caim. As the game progresses, her insults become less and less frequent as she realizes that her bond with Caim has allowed her to grow stronger than she ever was before. She eventually comes to love Caim, and becomes 'the defender' from the Analysis page. Caim triggers her 'deredere' side by the end of the game.
Angelus: (level 1) "Humans are a race to be pitied." "Wise men choose death before war. Wiser men choose not to be born." "Must you slaughter so many?" "The Seeds of Resurrection? Humans twist even the myths to their own purposes."
Angelus: (level 2) "Stare too much at the back of your shield, and you may begin to forget the enemy." "More myths! Why are humans so quick to hide from truth in castles made of clouds?" "Surely even you feel horror at this bloodshed. Or perhaps you do not." "I understand your passion. But should you slaughter with such reckless abandon?" "The one-eyes are defeated. Now to hunt the rest of the jackals. Your favorite sport, Caim..." "They crawl out of the earth like worms!" "Caim! Be strong! The world itself is in mortal danger!"
Angelus: (level 3) (after being hit) "Ugh! It is nothing. It is you who should take care, Caim." "Mighty dragon! You will regret challenging fools such as we!" "I thank you, Caim. I have become far stronger than I ever imagined." "Nothing is stronger than we are now. Let nothing that values life stand before us!" "Fools! You have no power against us!" (after Caim is at half health) "Are you alright?! You must be strong!"
Lulu from Final Fantasy X, but only towards the men in the party; Yuna and Rikku she treats like little sisters, and she doesn't really interact with Kimahri or Auron, leaving Tidus and Wakka. Towards them (Wakka in particular) she is usually very harsh, aside from a few moments when she shows a sweeter side; most notably, in Luca, she holds Wakka up when he's too exhausted to stand (despite being half a head taller and much heavier), and compliments his performance in the game. By the sequel, the two of them are hitched, expecting a child, and she's almost completely lost her tsuntsun side.
Another Code: Ashley Mizuki Robbins is normally a nice person to be around, but when she loses her temper, she stops listening to others and has a bit of a hissy-fit.
Rebecca The Archer is very tsuntsun towards her childhood friend Wil and Chivalrous Pervert Sain (showing extreme jealousy when they talk about their lady-in-liege, the aforementioned Lyndis, and even kicking Wil for it once-and for not remembering her from their childhood), yet in presence of Big Eater and fellow Team Chef Lowen she is absolutely deredere (to be fair, he didrescue her once...). Her deredere side also shows in her supports with Louise, whom she fangirls shamelessly, and the other girl around her age in the army, Nino.
The Pegasus Knight Karin from the fifth game is arguably a tsundere, specially in her interactions with Felgus or Eyrios.
Chihiro Fujimi in Persona 3 is a very mild example. Normally the Shrinking Violet, her social link reveals that she can snap and get very confrontational when protecting things she cares about (the subject in question being the main character).
Unlike most Tales Series characters who fit more in the harsh-but-sweet mold, Cheria Barnes of Tales of Graces is very much this way. She is mostly sweet and docile, even to her love interest Asbel. However, she gets harsh whenever someone points out her obvious crush, or if he ignores her affections, resulting in her snapping at him. Though, given what Asbel is like, you can't exactly blame her.
Princess Zelda in The Legend of Zelda: Spirit Tracks is the first example of this kind among Link's allies.(Ruto, Tatl, Tetra and Midna were all Type A) This Zelda may seem sweet as sugar and extremly polite when nothing is bothering her, but once something starts bothering here, you'd better pray that you're a) nowhere near her and b) not that poor guy named Link... She has a pretty loud shouting-voice and when she has a devasting weapon on hand, while snapping into Tsun-Tsun mode, she will use that weapon on whatever is annoying her. Although it is pretty justified when the cause for her outburst happens to be a certain whipof Link. Also there's Ilia from Twilight Princess
Jessica D'Alkrik from Lunar: The Silver Star (and its remake) is most definitely this. She's extremely hyperactive and somewhat forceful, but her default mood is cheerful and kind and plenty of NPCs in Meribia confirm she always has a kind word for them. Her tsun-side is reserved for those whose general behavior irritate her. (Nash at first, then Kyle once he joins and Nall on occasion) The reason her tsun-side becomes so obvious is because Kyle is attracted that side of her and can't help provoking her whenever he gets the opportunity.
Lavie Regale from Love And War is generally kind, friendly and cheerful, but if you push the wrong buttons, especially if your name is Ryan Eramond, then you're in trouble.
Monkey Pink from the Ape Escape series changes her attack patterns depending on whether she's cheery or enraged.
Viconia DeVir in Baldur's Gate: Shadows of Amn, if the player creates a male protagonist and engages in her romance subplot. Probably at least partly because she comes from an entire race that Does Not Like Men, and partly because she's just plain evil.
Cordelia von Feuerbach from Atelier Rorona, is basically a tsundere towards the game's main protagonist, Rorolina "Rorona" Frixell.
On the other hand, in the sequel, Atelier Totori, Mimi Houllier von Schwarzlang is entirely tsundere towards Totooria "Totori" Helmold, especially toward the fact that Totori is the daughter of a famous adventurer.
Etna from Disgaea, though it's only particularly apparent in the "Etna's Diary" subplot.
She does have intriguing notions on how to treat Prinnies though. (Not to mention all the weapons she broke trying to wake up Laharl.)
Laharl himself is the real tsundere. He's not only a rare male example, but a textbook case. Etna is quite a bit more open than he is, freely admitting she was concerned about Flonne. She just happens to be horribly abusive as well.
Even Flonne ends up looking sweet-but-harsh for much of the game, which is a testament to just how infuriatingLaharl can be. (Actually, it's because she's such a Love Freak that she ends up getting mad at Laharl so often.)
Fuka: [Fenrich]'s a tsundere! I've never seen one in real life before.
Iori Minase from The iDOLM@STER (it's Rie Kugimiya, alright) is a rare A/B hybrid — (mostly) friendly to fans and strangers, but (mostly) rude to the staff, her fellow idols and even the Producer.
Tron Bonne in Mega Man Legends. One boss fight consists of her trying her damnedest to get Megaman to 'dump' Roll and go for Tron instead, while attempting to murder him at the same time.
Meryl Silverburgh from the Metal Gear series, especially in the fourth installment. Her interactions with Johnny [Akiba] in the Outer Haven Shootout are perfect examples, especially when she decides to don the seme pants.
Meryl was one way back in Policenauts, which was full to the brim with fanservice (and even used the Tokimeki MemorialDating Sim engine). For most of the game, she's pretty aloof and very, very butch, but after her best friend (a TokusatsuOtakuTechnical Pacifist) is murdered, she softens up and even cries, agreeing to use the expensive, girly designer handbag Dave brought her, gets Dave's favourite flowers imported despite hating flowers herself - but remains very manly when she isn't thinking about him. When you remember that her character was originally intended as a Distaff Counterpart-slash-Expy of Metal Gear's Solid Snake, logical conclusions start gettingweird.
Solid Snake is pretty much a harsh-but-sweet type himself.
Male example: Azai Nagamasa in Sengoku Basara. He just HAD to keep up his Justice Freak in front of his introverted wife Oichi, so he tells her to shut up often when she starts moping around. But when nobody's around, he turns away and presents a flower for her.
Seolla Schweizer in of Super Robot Wars Alpha 2 hits the second type: friendly, professional, and kind of sweet to her peers and comrades, except she's constantly infuriated by her combat partner/love interest Arado Balanga, due to him playing the Idiot Hero / Crouching Moron, Hidden Badass (depending on continuity). Katina Tarask, on the other hand, seems like the first kind, but has no occasion to be deredere...period. Lampshaded by the fandom for giving her the Fan Nickname "Angry Desu".
Prier from La Pucelle Tactics behaves this way towards just about all the men she encounters, but especially towards her brother Culotte and, to a lesser degree, Croix.
Lady Sylvanas from the Warcraft series can be seen as a tsundere. While she is the leader of the undead Forsaken and outwardly seems like a cold, uncaring person, she shows a hidden soft side during some moments in the fluff (especially towards the blood elves), and the resolution of one quest in World of Warcraft shows Sylvanas mourning the loss of her sister and her "past" life when she sings The Lament of the Highborne. Before that song, if you give her the necklace, she shows surprise about the memories of her sister... then realizes that she's doing fluff in front of the undeads, so she quickly displays her cold attitude back and shoos you away... then sings that song. She really runs from hot, cold, and then hot again!
Meilin from Terranigma probably counts. A Mood-Swinger in the extreme, she can not decide what she thinks about Ark. The first time they meet, she hates him for spoiling her illusion of her dead parents. Then, she kind-of-stalks him around the woods and follows him while trying to make him notice her romantically, before eventually having a Face-Heel Turn, albeit one quickly reversed. Did we mention that she's quite a bit youngerthan Ark◊?
Kei Nanjo from Persona has one moment of Tsundere. He's mostly a ruthlessly pragmatic, efficient boy, always offering to pick up with the Sadistic Choice, and belittles Masao very often. At one point of the game, however, his ruthlessness becomes pivotal in getting the Ideal Maki to regain herself and gets thanked in result. He then suddenly goes into shy/dere-dere mode to the point that Masao points out that he should be glad that this is the first time somebody thanked him, resulting in Kei snapping back to tsun-tsun.
Hector in Fire Emblem: The Blazing Sword shows his soft side more easily around his three bridal choices and Eliwood.
Forget Hector, what about Prince Innes from Fire Emblem: The Sacred Stones? Quite the Jerk Ass sometimes, but a textbook tsundere for Eirika and L'Arachel. And considering that the latter is a tsundere too, they pretty much compete to see who's more tsuntsun or more deredere.
Ayra from Genealogy of the Holy War is jerkish and seemly uncaring toward Lex in their supports, but she is totally sweet and happy when she is paired with either Howlyn or Arden. By normal condition, she is a tough Action Girl who is protective toward her little brother.
Bastila, if the player character is male is often like this. Naturally, it took HK-47 to say what we were all thinking.
"Mockery: Oh, master, I love you but I hate everything you stand for, but I think we should go press our slimy, mucus-covered lips together in the cargo hold!"
She might actually count as a Type A given her interaction with other party members (especially Carth)
Alice Margatroid from the Touhou games is often depicted as this toward Marisa Kirisame in fanworks. Which type she is varies depending on who's writing the story at the time.
An official tsundere can be found in the semi-canon Inaba of the Moon and Earth. In it, Fujiwara no Mokou acts flagrantly tsundere towards her eternal enemy Kaguya Houraisan. She's a Type-A.
Parsee Mizuhashi, being a youkai of jealousy, is also often depicted as a tsundere towards Yuugi Hoshiguma. Like Alice, she varies between Type A and Type B, and still other fanworks portray her as a full-blown Yandere (consistent with the original hashihime, on whom she is based).
Pokémon Mystery Dungeon: Explorers of Time/Darkness/Sky features both types as two of your guildmates. Loudred is a bossy Tsun-tsun towards everyone, but especially towards Sunflora, who's dere-dere towards everyone but him. Naturally, this is highlighted in Sunflora's special episode in Sky, where Loudred pulls a Big Damn Heroestwice.
Ashara From Star Wars: The Old Republic's Inquisitor Storyline comes across as this Partially if you romance her as a male inquisitor.
Elika from Prince of Persia (2008) is a odd case. She's nicer than most Type-A's and not violent. Just really snarky. She shows Suspiciously Specific Denial once but even then it was subtle. However her dere side shows the further you get starting with actually showing she likes it when you catch her (a rather joyful laugh or teasing comment) to screaming "NO!" in complete horror when you miss a jump before she saves you or standing closer to you.
I wish you'd run out of coins so you can stop respawning and harassing me... Do something productive and get back to Tsundere!