Xanthus gained his royalty by making the decision humanity would die. In Sonic - The DCV, he had taken over Mobius for his own as his kingdom.  When disguised, Xanthus resembles Sonic the Hedgehog, though with some noticeable differences. This includes two piercing yellow eyes and an unnaturally wide grin, the overabundance of teeth stretching all the way to his ears.  Xanthus' true form makes his quills black and his fur purple. And his gloves dark red with gold bracelets.