In the Nintendo DS remake of Super Mario 64, Wario is a playable character. He, Mario and Luigi go to Princess Peach's castle for a party, but are instead captured by Bowser and locked away inside the castle. He is eventually freed by Luigi.
He is the strongest character out of the four that are playable, although he is also the slowest and has the worst jump. He is the only one can become metal, with the same abilities as Metal Mario in the original version of Super Mario 64.