Mikaeus, the Unhallowed + Grim Poppet + Ravenous Intruder

Mikaeus, the Unhallowed

Grim Poppet

Ravenous Intruder

How it works

1. Activate Ravenous Intruder by sacrificing Grim Poppet.
2. When Grim Poppet dies, its undying ability triggers, returning it from your graveyard to the battlefield without a +1/+1 counter on it due to its replacement effect.
3. Resolve the Ravenous Intruder ability
4. Repeat.

This clever loop relies on Mikaeus, the Unhallowed granting undying to Grim Poppet, ensuring that every time the Poppet hits the graveyard, it returns to the battlefield fresh with no counters on it. You trigger this endless cycle by using Ravenous Intruder to repeatedly sacrifice the Grim Poppet as an artifact creature, which simultaneously pumps the Intruder to terrifying proportions. While the combo doesn't strictly need the Poppet's counter-moving ability to loop, the synergy transforms simple artifact sacrifice into a perpetual motion machine of death, rebirth, and infinitely scaling power.