This is simply the greatest screenshot. Ever.
Capcom vs. SNK 2: Mark of the Millennium 2001 (2001 - Capcom - DC, PS2, GCN, XB)
If you were to ask a fighting game fan what the best 2D fighter was pre-2009, it's a 50/50 chance you'd be told without hesitation to seek out this absolute gem of a game. Featuring 49 characters from across the board of Capcom and industry rivals SNK's respective catalogues and an accessible Street Fighter style fighting system, it's virtually unbeaten even now, nearly a decade after it's release. And it provided me, at least, with a means to get to know SNK's cast with a familiar control method, instead of admiring them from afar in the past.
Marvel vs. Capcom 2: New Age of Heroes (2000 - Capcom - DC, PS2, XB, PS3, 360)
The other half of those fighting game fans would direct you to this stroke of genius from a year prior. MVC2 featured an even larger roster of 56 fighters including three original Capcom creations and 28 of Marvel Comics' expansive roster of heroes and villains, and an over-the-top fighting system featuring screen-filling special moves, strikers and tag fighting and a higher y-axis for super-fast midair combat. It's a little bit rare and pricey to find on disk now, but was re-released on XBox Live Arcade and PSN last year with a shiny HD filter, so it's readily available without even leaving the house. Nope, you have no excuse.
Mortal Kombat vs. DC Universe (2008 - Midway - PS3, 360)
I was convinced my home was bugged for a while after this was announced, as Mortal Kombat and DC Comics are too of my favourite things. Almost a polar opposite to the last game, and 8 years too late really, this 3D fighter pits the furious, visceral Scorpion, Sub-Zero and co against the heroes and villains of DC comics, led by the iconic trinity of Superman, Batman and Wonder Woman. The game was derided by players for the unlikely setting (because MVC2 was far more believable) and toned down gore, but was actually a very solid fighter, the best in the Mortal Kombat series in years in fact. It featured a cinematic story-driven single player mode, a solid multiplayer only flawed by a certain Superman move, and some fantastic universe-bending artwork in the endings. And most of the people who sneer haven't even played it, so give it a chance.
And before that, this was the greatest screenshot ever.
Tatsunoko vs. Capcom: Ultimate All-Stars (2009 - Capcom - Wii)
The latest in Capcom's versus series features a smaller cast of 26, but is the first to make the transition into 3D visuals. At first it seemed there was little chance of seeing this game released in the west due to licensing issues, but when it finally arrived we got an updated game with extra characters and a more refined system. Capcom draw on characters from games new to the Capom vs. series, such as Lost Planet, Dead Rising and Viewtiful Joe, And the Tatsunoko side is filled with legendary characters from classic 70's anime like Hurricane Polymar and Science Ninja Team Gatchaman (Battle of the Planets to us). The gameplay harks back to the MVC2 system, so if you're a Nintendo purist it's unmissable. But you really need a classic controller to get the most out of it, so things could prove pricey.
SNK vs. Capcom: SVC Chaos (2003 - SNK - PS2, XB)
Much like Namco is threatening to do, SNK released this retaliation to CVS2 using their own system and mechanics. Although it featured a drop in the roster count and was less in-your-face presentation-wise, SNK showed a willingness that Capcom hadn't by redrawing all of the characters' sprites, and drawing from a more fantastical cast including Metal Slug's Mars People, Red Earth's Tessa and Darkstalkers' Dimitri. I'll admit, I still haven't gotten my head around the SNK system, and they don't seem to have gotten the Capcom characters' personalities right in the conversation scenes, but it's still enjoyable, especially if you appreciate the art style.
Super Smash Bros. Brawl (2008 - Ad hoc - Wii)
Still one of the best Wii exclusives, SSBB pits characters from all of Nintendo's franchises against each other, from major players like Mario and Zelda, to lesser known games such as Mother and Fire Emblem, and even some from 3rd party games like Sonic the Hedgehog and Metal Gear. The game offers a unique fighting experience, focusing on ring-outs instead of KOs, the chance of which happening is displayed as a percentage instead of a health bar. Characters can also pick up and use powerups and weapons in the field, and the action is broken up by some absolutely beautiful FMV sequences. And it's another good reason to own that classic controller too.
But before that one, this was the best. Ever.
SoulCalibur II (2003 - Namco - PS2, XB, GCN)
Though not technically a crossover game, SCII has one exclusive character for each system, all from other franchises. The PS2 version has Tekken's Heihachi Mishima, the XBox homes Image Comics' Spawn and the Gamecube version naturally features Link from The Legend of Zelda. Most of you have played a SoulCalibur game, so you'll know all about it's weapon-based combat and genre-crossing story modes, but for those who haven't, think Tekken with swords and ring-outs. If you're looking for something more recent, check out SoulCalibur IV on the PS3 and 360, which features Darth Vader, Yoda and Galen Marek from Star Wars, and SoulCalibur: Broken Destiny on the PSP, which plays host to God of War's Kratos.
Marvel Nemesis: Rise of the Imperfects (2005 - EA - PS2, XB, GCN, PSP, DS)
Basically Marvel vs. EA, this game was largely forgettable on all versions except for the PSP, which dropped the scrolling fighter levels in favour of an experience similar to Power Stone and Ehrgeiz, and gave the Marvel Characters more of an iconic look. The EA side of things, the titular Imperfects, weren't classic EA characters, but rather a team of superhumans created by EA specifically for the game. Possibly not an essential purchase, but it is still the only fighting game that features Marvel characters such as The Thing, Elektra and (in the home console version at least) Daredevil, unless any of them make it into MVC3.
Jump Ultimate Stars (2006 - Ganbarion - DS)
A Japan-only release due to similar licencing hell to TVC, JUS would have fallen through the 24HG net had it not been for the absolutely monstrous character count; 305 (56 fully playable, the rest as strikers and support characters) of the protagonists and antagonists of the insanely popular (in the west also) Shonen Manga label, including Dragonball, Naruto, Bleach and One Piece, are crammed onto a single DS cart. The game plays similarly to Super Smash Bros., only with a completely baffling (especially so considering the Japanese text) card-based system. Even thinking about it makes my head hurt, but this is a grade-A fanboy wet dream.
MUGEN (1999 - Elecbyte - PC)
Apparently, to those pedantic competitive fighting game purists (read: wankers), MUGEN is an unbalanced abortion. But to the rest of us, it's a wonderful bit of freeware. Out of the box, so to speak, it's a basic 2D fighter with only one character, the generic Ryu-alike Kung Fu Man, but MUGEN offers those with a little bit of know-how to download and import a plethora of user created characters, some ripped from other games, some edited to become new characters, some created from scratch, and all with AI and a quality only limited by their creator's expertise. This is, however you look at it, the only place where you can see Sub-Zero decapitate Knuckles the Echidna, or Lobo stove in Thundercats' Lion-O's face. And that should be enough to sell it to anyone interested in the genre.
So, there are ten games to keep you occupied until Spring rolls around once more. There are more if you look for them too, like Capcom Fighting Jam (Capcom vs. Capcom), NeoGeo Battle Coliseum (SNK vs. SNK) and Spectral vs. Generation (Spectral Force vs. Generations of Chaos, me neither) all worth a play. So go forth, fight fans, and collide some worlds. Excelsior!