Fabio, Evanescent Prince

Whenever you cast a spell exile Fabio, Evanescent Price until the end of the current phase.
Whenever Fabio, Evanescent Prince enters the battlefield, it deals 1 damage to target creature.
Whenever Fabio, Evanescent Prince deals combat damage
to a player, exile target creature that was dealt damage this turn with a slime counter on it.
You may cast exiled spells with slime counters on them and spend colorless mana as though it were mana of any color to cast those spells.

"Goo Goo Ga Ga" - Fabio