Deoxys (デオキシス, Deokishisu, pronounced /di'ɑks.ɪs/) is a fictional creature in the Pokémon media franchise.
As a Poké Ball Pokémon
The Attack Form of Deoxys appears in Super Smash Bros. Brawl. When it comes out of its Poké Ball, it will fly upward, meteor smashing anyone who touches it, and will proceed to shoot a powerful Hyper Beam downwards, sending anyone that touches the beam to go flying with force, and if the opponent is close enough, it can suck them in with a strong force. When the blast gets slightly narrower, it OHKOs any opponent that touches the beam. Deoxys's attack does not harm the summoner. It looks exactly like Lucario's Final Smash, but it doesn't appear in the center of the stage, and it doesn't attack close to ground.
A DNA Pokémon born through the DNA of a space virus. It has multiple forms, and the abilities it possesses and the techniques it can remember change from form to form. It has four formes: Normal, Attack, Defense, and Speed. It can be made to change forms by using the power of a meteorite in Veilstone City.
In Super Smash Bros. Wii U/3DS
This Psychic-type Pokemon was born from a virus attached to a meteorite. It has four different Formes, but in Smash Bros. only the Attack Forme appears. In battle, it'll soar skyward before unleashing a powerful Hyper Beam attack straight downward from the crystal in its chest.