Hydro-Man, Fluid Felon{U}{U}

Legendary Creature — Elemental Villain

Whenever you cast a blue spell, if Hydro-Man is a creature, he gets +1/+1 until end of turn.
At the beginning of your end step, untap Hydro-Man. Until your next turn, he becomes a land and gains "{T}: Add {U}." (He's not a creature during that time.)

2/2

Illustrated by Borja Pindado