This is a moveset I made over in the Desperation thread. Since it's for Victini, I may as well bring it over here.
Victini w/ Choice Scarf + Victory Star
Hasty/Naive nature. 252 HP, 252 Speed, 6 Sp Atk
-Desperation (that is what it's called, right?)
-Brick Break (If only he got Superpower/Close Combat...)
100 base speed, 252 speed Evs, a speed+ nature and a Choice Scarf. So pretty frelling fast. I'm pretty sure the only things he won't outspeed are enemies with >100 base speed and either a Choice Scarf or a +2 boost. Desperation combined with that speed lets him come in and go off like a bomb, especially with 252 HP Evs. Overheat is another powerful option if you aren't quite ready to sacrifice him to the greater good, Brick Break deals with Blissey (If only he got one of the two moves I suggested), and Shadow Ball deals with Ghosts hoping to come in for free and/or make him kill himself for nothing.
EVs are for speed and maximum output from Desperation, with the extra dumped into Sp. Atk for a stronger Overheat and Shadow Ball. Oh, yes. If you do go with Focus Blast over Brick Break, run a Timid nature.