Choose from what the game shows
Ryūjin is a documented example, but a complete official species list is not publicly confirmed. Use the live customization menu as the authority and avoid third-party lists that add fan-made options.
Roleplay beyond the label
Give the character an occupation, home, relationships, and goals. Ask before making supernatural abilities affect other players, and separate personal lore from confirmed game mechanics.
Separate confirmed mechanics from community lore, and verify live details in Roblox.