In both ''VideoGame/XMenChildrenOfTheAtom'' and ''VideoGame/MarvelSuperHeroes'', Capcom inserted one of their characters ([[Franchise/StreetFighter Akuma]] in ''X-Men'', [[Franchise/{{Darkstalkers}} Anita]] in ''Marvel Super Heroes'') as {{Secret Character}}s. ''VideoGame/StreetFighterAlpha'' featured a hidden fight wherein Ryu and Ken faced off 2-on-1 with M. Bison. Sensing the potential for a moneymaker in those two disparate ideas, Capcom soon developed a full-fledged multimedia crossover with a tag team focus, and in 1996, it unleashed ''X-Men vs. Street Fighter''.

The 17-character playable roster includes Cyclops, Wolverine, Storm, Juggernaut and Magneto from ''Children of the Atom''; Ryu, Ken, Chun-Li, Charlie, Dhalsim, Zangief, M. Bison, and (not-that-hidden character) Akuma as they appeared in the ''Street Fighter Alpha'' titles; and the Capcom fighting game debuts of Gambit, Rogue, Sabretooth, and Shadaloo-era Cammy.

''[=XvSF=]'' introduced the tag-team fighting dynamic that became the trademark for the VideoGame/CapcomVsWhatever series of games: players choose two fighters, then switch between them on the fly in the middle of battle. This removes the usual best-of-three-rounds structure started by ''Street Fighter'' in favor of a one-round fight, as the fight ends when one side loses both fighters. Each teammate 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 two-person Hyper Combo where both fighters on a team perform a Hyper Combo at the same time for massive damage... provided the team still has both fighters available, of course.

The game had a non-existent story to back up the action; a player's chosen team would simply fight their way through various CPU-controlled teams before facing down a gigantic version of ''X-Men'' villain Apocalypse. (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, and if you win the fight, you see that character's ending.

Capcom followed this game with 1997's '''VideoGame/MarvelSuperHeroesVsStreetFighter'''.

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!! ''X-Men vs. Street Fighter'' contains the following tropes:

* 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 [[VideoGame/MarvelSuperHeroesVsStreetFighter later]] [[VideoGame/MarvelVsCapcomClashOfSuperHeroes games]]. It also serves as the basis for Charlie's much darker characterization and enhanced abilities in ''VideoGame/StreetFighterV'', though there it is the result of betrayal (as per his ''[[VideoGame/StreetFighterAlpha Alpha 2]]'' ending) and Charlie's subsequent revival at the hands of [[VideoGame/StreetFighterIII the Illuminati]].]]
* AssistCharacter: [[BadassFingersnap With a snap of his fingers]], Sabretooth can call for Birdy ("Birdy!"), his partner at the time in the comics whose telepathy had a pacifying effect on him, to step into the fray ("Yes, Boss!") and light up Sabretooth's opponent with her [[{{BFS}} oversized firearm]]. He even has a Hyper variant where Birdy fires off a volley of rounds.
* AttractMode
* BadassInDistress: [[http://www.vgmuseum.com/end/arcade/b/xmvsfsto.htm 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 for 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 ending has her being invited to join the X-Men. Ryu is also invited to join both the X-Men (in this 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!"'' [[labelnote:Translation]]"I am the best!"[[/labelnote]]
--> ''"La tournament est fini."'' [[labelnote:Translation]]"The tournament is over."[[/labelnote]]
* BlindIdiotTranslation: [[http://rq87.flyingomelette.com/RQ/Marvel/XSF/faq.html A number of the translations here are a bit spotty.]]
* BlowYouAway: Storm uses wind attacks as a few of her specials, and combines it with AnIcePerson for one of her Hypers.
* CallingYourAttacks: You'd expect this with the FightingGame characters, naturally. But it even extends to the Marvel {{Superhero}}es, among others.
--> '''''[[ComicBook/XMen BEHOLD!]] [[ComicBook/{{Cyclops}} OPTIC BLAST!]]'''''
* TheCameo: Many characters from both universes make appearances in the endings and stages.
* CombinationAttack: Double Hyper Combos, known in-game as a Variable Combination. In the original arcade release and Saturn port, these moves would also cause the player to [[SwitchOutMove tag out]] to their partner on standby.
* CounterAttack: Variable Counters. Like the Alpha Counters of ''Street Fighter Alpha'', they require the player to input a certain command while blocking at the cost of meter, though this will call in the second member of a team to jump in to deal the retaliatory blow. As with Variable Combinations, all versions sans the [=PS1=] port allow the player to swap places with their teammate in the process.
* 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 [[LetsYouAndHimFight must then fight his tag partner in a one-on-one match]]. This turn of events goes unexplained.
** FightingYourFriend: In the event that the two characters have some kind of positive rapport with one another, as suggested by several of the endings.
* EarlyBirdCameo: This game introduced Shadaloo-era Cammy (aka Killer Bee) before the ''VideoGame/StreetFighterAlpha'' series did.
* EverythingsBetterWithSpinning: Zangief.
* ExcusePlot: Random... ahem... street fights due to the interdimensional rift. The instruction manual for the [=PS1=] version expands on this by stating that various mutants and street fighters have mysteriously disappeared, with rumors placing the blame on either Bison or Magneto, so many of the playable characters have teamed up to investigate, [[GoodVersusGood though not]] [[HeadbuttingHeroes without some]] [[EnemyMine teamwork issues]]. See BadassInDistress for the closest to a concrete excuse aside of that.
* 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.]]
* 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."]]
* AnIcePerson: Storm in some of her attacks.
* 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]] (or in Akuma's case, the [[DangerousForbiddenTechnique Shun Goku Satsu]] itself).
* PoweredArmor: Apocalypse.
* PsychoticSmirk: Though his sprites are lifted from the ''Alpha'' series, Bison's normal stance is changed for this series to always wear one of these.
* RecurringRiff: While none of the assorted X-characters have their themes from that game carried over, the character select music is a remix of the one found in ''VideoGame/XMenChildrenOfTheAtom''.
* ShockAndAwe: Storm's primary form of offense. Many other characters have at least one shock/stun move.
* {{Shotoclone}}: Ryu, Ken, Cyclops, and Akuma.
* ShoutOut: Check [[ShoutOut/CapcomVsWhatever the page]].
* ShowWithinAShow: [[spoiler:In Ken's ending, we have him and his son playing the game before having dinner.]]
* {{Stripperific}}: On the ladies' side, Cammy. On 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 this feature, 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.

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