Eternal Scourge + Ashnod's Altar + Mimic Vat + Pawn of Ulamog

Eternal Scourge

Ashnod's Altar

Mimic Vat

Pawn of Ulamog

How it works

1. Activate Ashnod's Altar by sacrificing Eternal Scourge, adding CC.
2. When Eternal Scourge dies, Pawn of Ulamog and Mimic Vat trigger.
3. Resolve the Pawn of Ulamog trigger, creating a 0/1 Eldrazi Spawn creature token.
4. Resolve the Mimic Vat trigger, exiling Eternal Scourge from your graveyard.
5. Activate the Eldrazi Spawn by sacrificing it, adding C.
6. Cast Eternal Scourge from exile by paying 3.
7. Repeat.

This clever loop turns Ashnod's Altar into a self-sustaining engine by taking advantage of Eternal Scourge's unique ability to be cast straight from exile. Whenever you sacrifice the Scourge to the Altar, Pawn of Ulamog responds to the creature's death by churning out an Eldrazi Spawn token, while Mimic Vat conveniently holds the Scourge in exile just long enough for you to recast it. Sacrificing the generated Eldrazi Spawn provides the final piece of mana needed to cover the Scourge's casting cost, allowing you to seamlessly repeat the entire process for an endless stream of death, sacrifice, and entry triggers.