Colfenor, the Last Yew + Gutter Grime + Umbral Collar Zealot

Colfenor, the Last Yew

Gutter Grime

Umbral Collar Zealot

How it works

1. Cast the creature card in your hand by paying 0.
2. Either that creature dies as a state-based action due to having zero toughness, or activate Umbral Collar Zealot by sacrificing that creature.
3. Gutter Grime triggers, putting a slime counter on it and creating a X/X Ooze creature token.
4. Activate Umbral Collar Zealot by sacrificing the Ooze.
5. When the Ooze dies, Colfenor triggers, returning the creature card from your graveyard to your hand.
6. Resolve the Umbral Collar Zealot abilities, surveiling 1 each time.
7. Repeat.

This loop transforms the graveyard into an endless engine of growth by leveraging Colfenor, the Last Yew's ability to pull smaller creatures back to your hand whenever a creature you control dies. While Gutter Grime scales exponentially by turning every death into a growing Ooze token, Umbral Collar Zealot provides the crucial sacrifice outlet that keeps the cycle moving while feeding you an infinite stream of surveil triggers. By repeatedly feeding creatures and tokens into the Zealot, Colfenor effortlessly recursion-loops a zero-toughness creature to continuously pump your Oozes to astronomical proportions.