Underworld Breach + Malevolent Rumble + Cryptolith Rite + Garna, the Bloodflame

Underworld Breach

Malevolent Rumble

Cryptolith Rite

Garna, the Bloodflame

How it works

1. Cast Malevolent Rumble for its escape cost by paying 1 and exiling three other cards from your graveyard, causing you to mill at least three cards and create a 0/1 Eldrazi Spawn creature token.
2. Activate the Eldrazi Spawn by tapping it, adding .
3. Activate the Eldrazi Spawn by sacrificing it, adding C.
4. Repeat.

This loop relies on Underworld Breach turning your graveyard into a recursive casting zone, allowing you to repeatedly cast Malevolent Rumble from it for its escape cost by feeding cards to exile. To make those casts self-sustaining, Cryptolith Rite grants your creatures the ability to tap for mana, ensuring the Eldrazi Spawn tokens created by Malevolent Rumble can help pay for subsequent spell loops. Finally, Garna, the Bloodflame steps in as the engine's heartbeat: its triggered ability returns creature cards put into your graveyard from anywhere that turn straight back to your hand, fueling a near-infinite chain of creature entries, deaths, and self-mill.