Ritual of Slime

{b/g}{b/g}: Sacrifice a non-token creature to create
a 1/1 green and black Ooze creature token with:
"If this creature leaves play, draw a card."
You may only use this ability once per turn.
"The essence and the knowledge of a being is distilled
into pure Ooze so the great cycle of slime can continue
while the knowledge finds its way towards others."