Six Shield Emperor (六楯帝; rikujyuntei) is a family in the Battle Spirits trading card game.
Currently, the only card in this category is The SixShieldEmperor Kei, and it will likely remain that way.
Its name, the "Six Shield Emperor (六楯帝)", means the emperor of the six shields (六楯), which are six countries that exist in the background lore of Heroes Saga. Kei, the owner of the family, has united all six countries and becomes the supreme ruler of the country together with her husband, Manaka. This is why she is given such family.