Thermopod + Naru Meha, Master Wizard + Ascend from Avernus

Thermopod

Naru Meha, Master Wizard

Ascend from Avernus

How it works

1. Cast Ascend from Avernus by paying 4
2. Holding priority, cast Naru Meha by paying its mana cost.
3. When Naru Meha enters, it triggers, targeting Ascend from Avernus.
4. Holding priority, activate Thermopod by sacrificing Naru Meha.
5. Resolve the Naru Meha trigger, copying Ascend from Avernus
6. Resolve the Ascend from Avernus copy, returning Naru Meha from your graveyard to the battlefield.
7. Repeat from step 3.

This clever loop begins by casting Ascend from Avernus with a high enough value of $X$ to target any necessary creatures in your graveyard, followed instantly by flashing in Naru Meha, Master Wizard to copy the spell upon entry. By sacrificing Naru Meha to Thermopod's mana ability while the copy is on the stack, you feed the loop with red mana while sending the Wizard back to the graveyard. The resolving copy of Ascend from Avernus then brings Naru Meha right back to the battlefield, restarting the entire sequence to generate infinite mana, sacrifices, and recursive triggers.