Zolthis, Deity of Wind

Flying. Indestructible.
At the end of your turn, if you control no blue creature with worship, sacrifice Zolthis, Deity of Wind.
{t}, Remove three worship counters among the creatures you control:
Counter target spell. If the converted mana cost
of that spell is less than the number of blue creatures you control with worship, untap Zolthis, Deity of Wind.