Not too bad, KOF XII is an entertaining fighting game, but it has a couple of issues.
The game has few features, those are Arcade, Versus and Online. Yes, that's all. The arcade mode is ridicilously easy. Which leaves Versus, a basic fighting mode for up to two players. Here you can have the 3 on 3 fights or the more classic 1 on 1 battles. The characters are varied and look really cool, the animation is really nice but not silky smooth and jagged edges are clearly visible, especially in HD. The game's 3 on 3 fights are interesting and encourages you to explore other characters and their abilites to construct your own "dream team".
The problems here are as follows, some special attacks seem practically impossible to execute, I know practice makes perfect but geesh. The game has very little replayability, no unlockable characters, no unlockable stages. The latter being particularly annoying since there are only 5 stages, one being a night-time variant of the first stage. So there are really only 4. Okay, I know, it's not like Smash Bros. where the stages play a big deal, here they're just background scenery, as it should be. But a bit more variety would've been nice. Presentation wise, the menus are bland and the same goes for the music. I haven't tested the online mode as I don't have an XBOX Live subscription as of the moment.
KOF XII is a decent good fighting game, however there are better ones out there, still, it gets the job done and manages to be entertaining. And really, for me, it's only something to keep me occupied until Tatsunoko vs. Capcom comes out.