I count Rotom as a legend to a certain extent as you can only catch one in the game.
Manaphy is a legend, and a badass one at that with it's Hydration.
Don't know if I would consider Phione as a legend, it's much weaker then Manaphy [But you could say the same of Rotom] but meh.
@toad: Take off Accupressure and go with Sword Dance for a buffer.
But try experimenting instead of going for default sets. You might surprise yourself.
Oh yeah, and pretty much ANYTHING can kill a Deoxys attack form in one hit. ._."'