In 1996, after some flirting with their characters as {{Secret Character}}s in both ''VideoGame/XMenChildrenOfTheAtom'' and ''VideoGame/MarvelSuperHeroes'', Capcom took the idea and ran with it, making a full-fledged crossover as '''X-Men vs. Franchise/StreetFighter'''.

The playable roster is composed of Cyclops, Wolverine, Storm, Juggernaut and Magneto from ''X-Men: Children of the Atom'', and Ryu, Ken, Chun-Li, Charlie, Dhalsim, Zangief, M. Bison and Akuma as they appeared in the ''VideoGame/StreetFighterAlpha'' titles. The game also marked the Capcom fighting game debuts of Gambit, Rogue and Sabretooth, as well as Shadaloo-era Cammy.

''XSF'' introduced the tag team fighting dynamic which became the trademark for the CapcomVsWhatever series of games: players choose two fighters and switch between them on the fly in the middle of battle, eschewing the usual two-round structure started by ''Street Fighter'' in favor of a one-round fight (the fight ends when both fighters on one team are eliminated). Each character has their own lifebar, and when switched out, the inactive fighter will heal some of the damage they've taken until called back into action. The game also allows players to use a deadly Double Super Combo where both fighters perform a Super Combo at the same time for massive damage.

The story was all but nonexistent, with the chosen team fighting their way through various team-ups before facing down Apocalypse in a slight genre change. (Though Storm's ending implies that Apocalypse has been abducting mutants and street fighters alike for undisclosed reasons.) After defeating Apocalypse, you fight against your tag partner using whatever character landed the final blow during the boss battle. So much for teamwork...

Followed in 1997 with '''VideoGame/MarvelSuperHeroesVsStreetFighter'''.

!!The game shows examples of:
* AGodAmI: M. Bison and Magneto's endings in ''X-Men vs. Street Fighter'' also have this. In the latter's case, [[spoiler:[[QuirkyMinibossSquad Sagat, Vega, and Balrog]] join him, switching from Shadaloo to the Acolytes.]]
* AllJustADream: [[spoiler: Dhalsim's ending. He actually dreamed the whole thing while he was neck deep in meditation, and wakes up when Sari and Datta call out for him.]]
* UsefulNotes/AmericanAccents: Rogue's winquotes are written with Southern accents.
* AndIMustScream: In Charlie's ending, [[spoiler:he's kidnapped by Shadaloo and [[FateWorseThanDeath gets attached to]] [[PlayingWithSyringes nasty experiments]]. Then we see Guile, who is searching for him.]]
** [[spoiler: This is foreshadowing of him [[BrainwashedAndCrazy becoming Shadow]] in later games.]]
* AnIcePerson: Storm in some of her attacks.
* AttractMode
* BadassInDistress: [[ Storm's ending]] reveals that [[spoiler: several X-Men and street fighters were captured by Apocalypse, though we don't know the exact reasons. (We can bet he intended to use them in experiments or try recruiting them into his cause.) We see Storm herself tending to her then-boyfriend Forge, while Sakura befriends Gambit and Dan Hibiki runs around in the background.]]
* BadassNormal: Zangief.
** Chun-Li's ''X-Men vs. Street Fighter'' ending has her being invited to join the X-Men. Ryu is also invited to join both the X-Men (in the aforementioned game) and the Avengers (in ''Marvel Super Heroes vs. Street Fighter''), but politely declines both offers.
* BigBad: Apocalypse.
* BilingualBonus: Some of Gambit's winquotes are written in French:
--> ''"Je suis le meilleur!"''
--> ''"La tournament est fini."''
* BlowYouAway: Storm uses wind attacks as a few of her specials, and combines it with AnIcePerson for one of her Supers.
* CallingYourAttacks: You'd expect this with the FightingGame characters, naturally. But it even extends to the Marvel {{Superhero}}es, among others.
--> '''''[[Comicbook/{{X-Men}} BEHOLD! OPTIC BLAST!]]'''''
* TheCameo: Many characters from both universes make appearances in the endings and stages.
* CombinationAttack: Double Supers.
* DeepSouth: Rogue, sugah.
* DuelingPlayerCharacters: In the single-player story mode, after defeating Apocalypse, the player takes control of whichever character landed the final blow and must then fight his tag partner in a one-on-one match. This turn of events goes unexplained.
* EarlyBirdCameo: This game introduced Shadowloo-era Cammy before the ''VideoGame/StreetFighterAlpha'' series did.
* EverythingsBetterWithSpinning: Zangief.
* EvilGrin: Though his sprites are lifted from the ''Alpha'' series, Bison's normals stance is changed for this series to always wear one of these.
* ExcusePlot: Random... ahem... street fights due to the interdimensional rift. See BadassInDistress for the closest to a concrete excuse aside of that.
* HuskyRusskie: Obviously, Zangief. [[spoiler: Taken UpToEleven in his ending, where [[BashBrothers he teams up]] with Piotr "Colossus" Rasputin to capture a recently escaped Arkady "Omega Red" Rossovich... meaning that we have '''three''' {{Husky Russkie}}s suddenly in the same place...]]
* IJustWantToBeNormal: In Rogue's ending, [[spoiler:Bison promises her that he will make her human if she joins him, something she rejects. Then, Rogue has a talk with Chun-Li, where she asks how it feels being human. Chun-Li answers that she can throw fireballs, and asks what's normal about that.]]
** Similarly, in Gambit's ending [[spoiler: she tells him about her woes, but Gambit hugs her and says "You're perfect JustTheWayYouAre".]]
* KamehameHadoken: The second part of the trope's name comes from the version of the Shinkuu Hadouken, which is the best known of many, MANY, '''MANY''' instances.
* KickChick: Chun-Li and Cammy.
* KissOfDeath: One of Rogue's special attacks, it allows her to [[PowerCopying steal an opponent's special attack]].
* PoweredArmor: Apocalypse.
* ShockAndAwe: Storm's primary form of offense. Many other characters have at least one shock/stun move.
* ShowWithinAShow: [[spoiler: In Ken's ending, we have him and his son playing the game before having dinner.]]
* {{Shotoclone}}: Ryu, Ken, Cyclops and Akuma.
* ShoutOut: Check [[ShoutOut/CapcomVsWhatever the page]].
* {{Stripperific}}: In the ladies' side, Cammy. In the men's side, Zangief and Dhalsim.
* SurprisinglyGoodEnglish: Cammy and all Marvel characters are voiced by native English speakers.
* TagTeam: It's the first game in the series which incorporates that, predating a lot of future games.
* TakeThat:
--> '''Sabretooth:''' This ain't no Franchise/{{street fight|er}}! You lose...
* ThereIsNoKillLikeOverkill:
--> '''''"HYPER COMBO FINISH!"'''''
* WorthyOpponent: What Wolverine considers [[spoiler: Ryu]] as.