Trident of Fish Command

Trident of Fish Command casts {x} more to cast,
where {x} is the total power of non-fish creatures
you control.
When trident of fish command enters the battlefield, create a 1/1 blue fish creature token
with: this creature cannot be blocked.
{1}{u},{t}: Create a 1/1 blue fish creature token
with: this creature cannot be blocked. If you already control a fish, untap Trident of Fish Command.