Wilhelt, the Rotcleaver + Shambling Ghast + Chthonian Nightmare + Pitiless Plunderer + Umbral Collar Zealot

Wilhelt, the Rotcleaver

Shambling Ghast

Chthonian Nightmare

Pitiless Plunderer

Umbral Collar Zealot

How it works

1. Activate Umbral Collar Zealot by sacrificing Shambling Ghast.
2. When Shambling Ghast dies, it, Pitiless Plunderer and Wilhelt's first ability trigger.
3. Resolve the Shambling Ghast and Pitiless Plunderer triggers, creating two Treasure tokens.
4. Resolve the Wilhelt trigger, creating a 2/2 Zombie creature token with decayed.
5. Resolve the Umbral Collar Zealot ability from step 1
6. Activate the Treasures by tapping and sacrificing them, adding 1.
7. Cast Chthonian Nightmare by paying 1.
8. When Chthonian Nightmare enters the battlefield, it triggers, causing you to get EEE.
9. Activate Chthonian Nightmare by paying E, sacrificing the Zombie token, and returning Chthonian Nightmare from the battlefield to your hand, returning Shambling Ghast from your graveyard to the battlefield.
10. Repeat.

This elegant loop centers on Chthonian Nightmare, which perpetually recycles Shambling Ghast from your graveyard by trading away energy and fodder. To keep the cycle going indefinitely, Pitiless Plunderer and Umbral Collar Zealot convert your sacrifices into the necessary mana and fodder, while Wilhelt, the Rotcleaver steps in to ensure your departed Shambling Ghast always leaves behind a decaying replacement Zombie token to feed the Nightmare's hunger.