Blightbeetle + Carrion Feeder + Harmless Offering

Blightbeetle

Carrion Feeder

Harmless Offering

How it works

1. Donate Blightbeetle to an opponent
2. Activate Carrion Feeder by sacrificing the undying creature.
3. When the undying creature dies, its undying ability triggers, returning itself from your graveyard to the battlefield without a +1/+1 counter on it due to Blightbeetle.
4. Resolve the Carrion Feeder ability.
5. Repeat from step 2.

This loop hinges on a clever piece of rules interaction made possible by Blightbeetle, whose static ability prevents your opponents' creatures from ever receiving +1/+1 counters. By using Harmless Offering to hand that Beetle over to your rival, their creatures are permanently stripped of their natural growth—including the counters that would normally reset abilities like undying. With this restriction locked in place, you can continually feed your creatures to Carrion Feeder, sacrificing them to pump it up while the undying mechanic brings them straight back to the battlefield completely unhindered by counter-based penalties.