Reaping Willow + Phyrexian Altar + Agatha of the Vile Cauldron + Chaos Spewer
Reaping Willow
Phyrexian Altar
Agatha of the Vile Cauldron
Chaos Spewer
Infinite creature ETBInfinite creature LTBInfinite death triggersInfinite creature sacrifice triggers
How it works
Activate Reaping Willow by paying W/B due to Agatha of the Vile Cauldron and removing two counters from it, returning Chaos Spewer from your graveyard to the battlefield.
When Chaos Spewer enters, it triggers, putting two -1/-1 counters on Reaping Willow.
Activate Phyrexian Altar by sacrificing Chaos Spewer, adding W/B.