Fate/Extra

Play this game. Not even remotely for the gameplay, I advise cheating to get through it. The story is just nutty as hell.

Do the Caster route. Please. God, please. I love Caster more than I love myself.

Also, follow a guide to get through the private room stuff, just so you can see everything that character has to offer.

While the ending is a little unsatisfying, I feel that everything else present more than makes up for it. I do despise the mana transfer scene, but that's getting removed/replaced in Extra Record, so I'm not too broken up about it.

Point is; I love Caster. Do the Caster route, or enjoy the next forty five seconds.