Lose their shiny Rayquaza (Japanese: レックウザ Rayquaza) is a dual-type Dragon/Flying Legendary Pokémon introduced in Generation III.
While it is not known to evolve into or from any other Pokémon, Rayquaza can Mega Evolve into Mega Rayquaza if it knows Dragon Ascent, but only if it is not holding a Z-Crystal. In Pokémon Omega Ruby and Alpha Sapphire, the Rayquaza featured in the Delta Episode must be caught (which requires it to eat the Meteorite) before the player can Mega Evolve any Rayquaza.
Rayquaza is the game mascot of Pokémon Emerald, appearing on the boxart of the game. It serves to end the conflict between Kyogre and Groudon when Team Magma's leader Maxie and Team Aqua's leader Archie awakened them.
Along with Kyogre and Groudon, Rayquaza is a part of the weather trio, serving as its trio master. In Omega Ruby and Alpha Sapphire, it plays an important role during the Delta Episode and is required to be caught there to fight Deoxys.