Mortuary + Experimental Frenzy + Priest of Urabrask + Thermopod

Mortuary

Experimental Frenzy

Priest of Urabrask

Thermopod

How it works

1. Activate Thermopod's second ability by sacrificing Priest of Urabrask, adding .
2. When Priest of Urabrask dies, Mortuary triggers, putting Priest of Urabrask on top of your library from your graveyard.
3. Cast Priest of Urabrask from the top of your library by paying 2.
4. When Priest of Urabrask enters the battlefield, it triggers, adding .
5. Repeat.

This engine turns a continuous loop of life and death into a fountain of red mana, all operating directly out of your library. Experimental Frenzy makes this possible by letting you cast spells from the top of your library while Mortuary ensures that any creature sent to your graveyard immediately goes back to the very top. Inside this loop, Priest of Urabrask provides the engine's fuel by generating more mana on entry than it costs to recast, while Thermopod acts as the sacrificial altar that converts each iteration into the red mana needed to keep going.