Shepherd of the Cosmos + Carrion Feeder + Fungal Fortitude

Shepherd of the Cosmos

Carrion Feeder

Fungal Fortitude

How it works

1. Activate Carrion Feeder by sacrificing Shepherd of the Cosmos.
2. When Shepherd of the Cosmos dies, Fungal Fortitude triggers, returning Shepherd of the Cosmos from your graveyard to the battlefield.
3. When Shepherd of the Cosmos enters the battlefield, it triggers, returning Fungal Fortitude from your graveyard to the battlefield attached to Shepherd of the Cosmos.
4. Resolve the Carrion Feeder ability, putting a +1/+1 counter on it.
5. Repeat.

This clever loop relies on an infinite recursion between the graveyard and the battlefield, starting with Carrion Feeder to sacrifice Shepherd of the Cosmos for a growing pile of +1/+1 counters. Every time the Shepherd hits the graveyard, Fungal Fortitude steps in with its replacement-style death trigger to immediately return the creature to the battlefield. That triumphant entrance triggers Shepherd of the Cosmos's own ability, pulling Fungal Fortitude right back out of the graveyard and re-enchanting the Shepherd to set up the next iteration.