Let's Talk about Crossovers

I noticed we hadn't had any sort of thread like this in recent memory, so I thought I'd bring it up. Crossovers are a pretty large part of gaming, with both inter-company and in-company crossovers forming some impressively strong franchises, such as the Capcom Vs. Whatever Series, Kingdom Hearts, Super Smash Bros., as well as several standalone games, like Pokemon Conquest and Theatrhythym Final Fantasy.

So the question is actually fairly simple, what are your favorite crossovers, what are your least favorite? Why do you think they work or don't? Do you just hate crossovers altogether?

Personally, may favorites include Capcom vs. Whatever, Kingdom Hearts, and Smash Bros. Kingdom Hearts is currently the freshest in my mind due to the recent release of Kingdom Hearts 3D: Dream Drop Distance, though I have taken to playing Marvel vs. Capcom 2 and Super Smash Bros. Brawl again recently. Of them, I feel Kingdom Hearts has the strongest story simply by virtue of being an Action RPG, while Brawl weaves something interesting with the Subspace Emissary, but, like most fighting games, is somewhat of an excuse plot for your favorite characters to smack each other around in spectacular fashion.

I can't overstate how much I love Kingdom Hearts. It is so friggin good. What I really like about it though is how the story's developed so much that it doesn't really feel like a crossover anymore. Basically Kingdom Hearts has so much story on its own now that it doesn't really need the Disney elements anymore. I've always cared more about the original story and the original worlds than the Disney bits anyway

I do enjoy the Super Smash Bros. series as well. Just like Tailon noted about the Subspace Emissary, it's just an excuse to mash up all your favorite heroes and villains, but that's not necessarily a bad thing. That's the one reason I absolutely loved the Avengers, all of my favorite superheroes joined up to kick some ass together And I have to admit that I grinned at the very end of SE, where Link and Zelda revive Ganondorf, and he joins them to fight Taboo