The rarity of Raikage Warrior is Mythical, and been equipped it takes a “Bundle” slot. At this moment the item is available for trade.
Raikage Warrior is a skin for Storm Spirit. The skin was added to the game on January 7, 2016, it was created by Jigglypuff.
Raikage Warrior has been recently added to the game, which makes it rather popular with the game community.