In Pokemon Ruby & Sapphire, FireRed & LeafGreen, and Emerald, contains various glitch Pokemon, that occupies the Gen III programmed index spaces of 252-276 (between Celebi and Treecko). All of their physical stats are exactly the same as the Pokemon Deoxys. Speculation is, the 25 slots originally contained fully formatted Pokemon, but was dummied out after. This Pokemon, ?, has the cry of Unown, and it's only ability is none (-------), it normally can only have the attack Tack