Recurring Nightmare + Phyrexian Altar + Deep Forest Hermit

Recurring Nightmare

Phyrexian Altar

Deep Forest Hermit

How it works

1. Activate Recurring Nightmare by sacrificing a creature and returning it from the battlefield to your hand, returning Deep Forest Hermit from your graveyard to the battlefield.
2. When Deep Forest Hermit enters the battlefield, it triggers, creating four 1/1 Squirrel creature tokens.
3. Activate Phyrexian Altar three times by sacrificing Deep Forest Hermit and two Squirrels, adding 2.
4. Cast Recurring Nightmare by paying 2.
5. Repeat.

This clever loop relies on Deep Forest Hermit entering the battlefield to flood your board with four 1/1 Squirrel tokens while conveniently bypassing its vanishing drawback through continuous recycling. You can then sacrifice the Hermit along with a couple of those tokens to Phyrexian Altar, generating the exact black and generic mana you need to pay for Recurring Nightmare's casting cost. Recurring Nightmare itself acts as the engine's beating heart, letting you sacrifice a creature to yank that very same Hermit right back out of your graveyard and onto the battlefield to restart the cycle.