Perfect Cell

Flying, ward {3}

When this creature enters the battlefield Cascade. (Exile cards from the top of your library until you exile a nonland card that costs equal or less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
{b}{g} Regenerate:Heal all damage enter the battlefield.

When you cascade create X 1/1 perfect blue mini cell tokens with flying and deathtouch where X is equal the spells mana value.