Thermopod + Dualcaster Mage + Graceful Reprieve

Thermopod

Dualcaster Mage

Graceful Reprieve

How it works

1. Cast Graceful Reprieve by paying its mana cost.
2. Holding priority, cast Dualcaster Mage by paying its mana cost.
3. When Dualcaster Mage enters, it triggers, copying Graceful Reprieve, with the copy targeting Dualcaster Mage.
4. Resolve the copy of Graceful Reprieve.
5. Holding priority, activate Thermopod by sacrificing Dualcaster Mage.
6. When Dualcaster Mage dies, Graceful Reprieve triggers, returning Dualcaster Mage from your graveyard to the battlefield.
7. Repeat from step 3.

This elegant loop relies on an infinite recursion of entering, dying, and returning to the battlefield to flood your mana pool and trigger your entire board. You kick off the sequence by casting Graceful Reprieve, then instantly intercepting it with Dualcaster Mage so its enters-the-battlefield ability copies the spell right back onto the Mage itself. From there, Thermopod steps in as the sacrifice outlet, converting the doomed Mage into red mana while sending it to the graveyard. That death immediately triggers the lingering replacement effect of Graceful Reprieve to bounce Dualcaster Mage straight back to the battlefield, ready to copy the spell all over again and net infinite red mana, sacrifices, and trigger effects.