Oh, both. In terms of stats, Nike has -def, and whole team +atk & heal while Cthulhu has -def & -atk, and black propaganda which are good when you're dedicating that account into water team. Sol is a dynamic Kami though, effective in every element. So basically: Dedicated water team (Nike, Cthulhu) or first water team, then decide to construct different elemental teams (Ryu-Oh, Sol) soon.