Reaping Willow + Ashnod's Altar + Agatha's Soul Cauldron + Defiant Greatmaw

Reaping Willow

Ashnod's Altar

Agatha's Soul Cauldron

Defiant Greatmaw

How it works

1. Activate Reaping Willow by paying 2 due to Agatha's Soul Cauldron and removing two counters from it, returning Defiant Greatmaw from your graveyard to the battlefield.
2. When Defiant Greatmaw enters, it triggers, putting two -1/-1 counters on Reaping Willow.
3. Activate Ashnod's Altar by sacrificing Defiant Greatmaw, adding CC.
4. Repeat.

This clever loop turns Ashnod's Altar into a self-sustaining engine by utilizing Agatha's Soul Cauldron to grant activated abilities across your board, letting you pay costs and color requirements smoothly with the Cauldron's mana-filtering effect. When you sacrifice Defiant Greatmaw to the Altar for colorless mana, Reaping Willow steps in to bring it right back from the graveyard. The magic happens because Reaping Willow's ability is fueled by removing its own counters—which Defiant Greatmaw conveniently replaces the moment it enters the battlefield, neatly resetting the cycle for infinite sacrifices.