Griseous Orb
A Griseous Orb is a held item that increases the strength of Giratina's Dragon- and Ghost-type moves by 20%. A Giratina that holds it will switch to Origin Forme until the item is removed. It has no effect when held by any other Pokémon.
It is a possible drop from Uncommon and Rare Boss Pokémon.
When used on a Timespace Altar that has been activated with a Red Chain, a Griseous Orb will summon Giratina.