Rainman

Cascade
Whenever a card is cast due to cascade flip a coin.
If heads create an X/X Elder Ferret Token with
Haste, Vigilance, Lifelink.
If tails create X 1/1 critter tokens with
{1}{t}Sacrifice this creature. Tap or untap target permanent.
X equals the cards converted mana cost.
This is far too abstract to be one of my dreams