Colfenor, the Last Yew + Sifter of Skulls + Hangarback Walker

Colfenor, the Last Yew

Sifter of Skulls

Hangarback Walker

How it works

1. Cast Hangarback Walker by paying 0.
2. Hangarback Walker enters the battlefield and dies as a state-based action due to having zero or less toughness.
3. Colfenor and Sifter of Skulls trigger.
4. Resolve the Colfenor trigger, returning nothing from your graveyard to your hand.
5. Resolve the Sifter of Skulls trigger, creating a 1/1 Eldrazi Spawn creature token.
6. Activate the Eldrazi Spawn by sacrificing it, adding C.
7. The Eldrazi Spawn dies, triggering Colfenor, returning Hangarback Walker from your graveyard to your hand.
8. Repeat.