Agatha's Soul Cauldron + War Elemental + Walking Ballista

Prerequisites

• War Elemental has at least one +1/+1 counter on it.

Steps

1. 1Activate War Elemental using Walking Ballista's second ability by removing a +1/+1 counter from it, dealing 1 damage to an opponent.
2. 2War Elemental triggers, putting a +1/+1 counter on itself.
3. 3Repeat.

Effects

• Infinite damage