Greythorne are a species of dolphin or whale-like animal that can be found all over the World of Baten Kaitos, oftentimes as pets. They exist is a variety of often bright colors.
Origins[]
In Origins the greythornes, like in the first game, are treated like pets and found around several areas, sometimes drawn to areas with mystical properties. There is also a sidequest where the heroes need to use Salty Walter to swap minds with them so they can talk to villagers and get more info on the story and magnus.
Eternal Wings Lost Ocean[]
In this game the grythornes are introduced as pets, and can be seen all around the world.
At the end of Baten Kaitos: Eternal Wings and the Lost Ocean it is revealed that the Greythorne were really the form taken by the Whale in exile while the Ocean was being kept safe within the Ice Queens. Once the Ocean is released back onto the purified Earth, the greythorne joined together once again to form the Whale.
One well known greythorne was Meemai, who traveled everywhere with Xelha.