Shay Cormac + Agatha's Soul Cauldron + Walking Ballista

Prerequisites

• Shay Cormac has at least one +1/+1 counter on it.
• You have a way to give Shay Cormac deathtouch.

Steps

1. 1Give Shay Cormac deathtouch, if needed.
2. 2Activate Shay Cormac using Walking Ballista's second ability by removing a +1/+1 counter from it, targeting a creature an opponent controls.
3. 3Shay Cormac's first ability triggers, putting a bounty counter on the targeted creature.
4. 4Resolve the Shay Cormac ability from step 2, dealing 1 damage to the creature and killing it due to Shay Cormac's deathtouch.
5. 5When the creature dies, Shay Cormac's second ability triggers, putting two +1/+1 counters on it.
6. 6Repeat from step 2.
7. 7If the method giving Shay Cormac deathtouch lasts indefinitely, you may repeat this loop whenever a creature enters the battlefield under an opponent's control.

Effects

• Destroy all creatures opponents control
• Destroy each creature that enters the battlefield under an opponent's control
• Lock