Cauldron of Souls + Dross Scorpion + Arcbound Ravager + Forsaken Monument

Cauldron of Souls

Dross Scorpion

Arcbound Ravager

Forsaken Monument

How it works

1. Activate Cauldron of Souls by tapping it, giving Arcbound Ravager persist until end of turn.
2. Activate Arcbound Ravager by sacrifcing itself.
3. The Arcbound Ravager ability fails to resolve due to Arcbound Ravager no longer being on the battlefield.
4. Arcbound Ravager dies, triggering its persist ability and Dross Scorpion.
5. Resolve the Arcbound Ravager trigger, returning it to the battlefield with zero +1/+1 counters due to its modular ability.
6. Resolve the Dross Scorpion trigger, untapping Cauldron of Souls.
7. Repeat.