Source: https://bulbapedia.bulbagarden.net/wiki/Deoxys_(Pokémon)

Deoxys (Japanese: デオキシス Deoxys) is a Psychic-type mythical Pokémon.

Deoxys is an alien-like bipedal Pokémon that has four Formes, each focused on a different stat. The main components that are constant for all four Formes are a dominant reddish orange color, a bluish-green face, and three bluish-green dots on its back arranged in a triangle. Typically, there is a purple stripe running down the center of its face and a purple, crystalline organ in its chest. Its white, circular eyes are set inside rectangular, black eye sockets. It is shown in the anime, that Deoxys may have a green crystalline organ and facial stripe.

In Gen III, the Forme it takes is dependant on which game it is in and can only be changed by trading. It appears in its Normal Forme in Pokémon Ruby, Sapphire, Colosseum and XD. In Pokémon FireRed it takes on its Attack Forme, in Pokémon LeafGreen the Defense Forme is the default, and in Pokémon Emerald it appears in Speed Forme. From Gen IV onwards, its Forme can be changed at will in Veilstone City, Kanto Route 3, Nacrene City, Ambrette Town, Fallarbor Town, or Hokulani Observatory.

Deoxys's appearance in Pokémon Omega Ruby and Alpha Sapphire at the end of the Delta Episode in the post-game marked the first time a Mythical Pokémon became available in-game without the need to attend an event or obtain a download code.

Deoxys was also the first Pokémon to have its own unique battle music. (Rayquaza's theme was the exact same as that of Kyogre and Groudon in Pokémon Ruby, Sapphire, and Emerald, and it wasn't until Pokémon Omega Ruby and Alpha Sapphire that it got its own theme; a rearrangement of the Kyogre/Groudon theme.)

Deoxys is also the highest-leveled scripted encounter that is legitimately obtainable, being level 80 when fought. (Arceus also appears at level 80 in the Hall of Origin, but it cannot be legitimately obtained.)

See Also:

• pokémon
• legendary_pokémon
• Generation III
• legendary_titans
• regirock
• regice
• registeel
• eon_duo
• latias
• mega_latias
• latios
• mega_latios
• weather_trio
• kyogre
• groudon
• rayquaza
• mega_rayquaza
• jirachi
• deoxys
• normal_forme_deoxys
• attack_forme_deoxys
• defense_forme_deoxys
• speed_forme_deoxys