Extruder + Lesser Masticore + Mm'menon, Uthros Exile

Extruder

Lesser Masticore

Mm'menon, Uthros Exile

How it works

1. Activate Extruder by sacrificing Lesser Masticore.
2. When Lesser Masticore dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. When Lesser Masticore enters, Mm'menon triggers, putting a +1/+1 counter on Lesser Masticore.
4. Resolve the Extruder ability.
5. Repeat.

This loop turns the cycle of life and death into a perpetual motion machine by weaponizing Lesser Masticore's persist ability. Whenever you feed the Masticore to Extruder's sacrifice outlet, it returns with a -1/-1 counter, but Mm'menon, Uthros Exile steps in upon its re-entry to drop a +1/+1 counter on it—which immediately neutralizes the -1/-1 counter through state-based actions. Because the persist counter is thus cancelled out, the Masticore is ready to die and persist all over again whenever you need to feed Extruder another sacrifice.