A Pseudo-Legendary is a Pokémon deemed as powerful as a Legendary Pokémon, but lacks any back story that said Legendary Pokémon might possess. These Pokémon typically have a three-stage evolution line, two types, are usually near the Legendary Pokémon in the Pokédex, and a total Base Stat of 600.
Related ThreadsWill the Pseudo Legendary be Fairy type? - last post by @ Jun 13, 2013
Favourite Pseudo-Legendary Pokemon? - last post by @ Jul 5, 2013
New Pseudo-Legendary - last post by @ May 3, 2011