Thermopod + Lingering Tormentor + Hardened Academic

Thermopod

Lingering Tormentor

Hardened Academic

How it works

1. Activate Thermopod by sacrificing Lingering Tormentor.
2. When Lingering Tormentor dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. Hardened Academic triggers, putting a +1/+1 counter on Lingering Tormentor.
4. Repeat.

This clever loop centers around Lingering Tormentor and Thermopod working together as a self-sustaining mana and sacrifice engine, where sacrificing the Tormentor produces red mana and triggers its persist ability. Because persist returns the creature with a -1/-1 counter, Hardened Academic steps in as the crucial enabler: whenever that persist trigger causes a card to leave your graveyard, its static triggered ability places a +1/+1 counter on the Tormentor. State-based actions immediately cancel out the opposing +1/+1 and -1/-1 counters, resetting the Tormentor so it can be sacrificed to Thermopod all over again for infinite red mana, death triggers, and sacrifice counts.