Sengir, the Dark Baron + Agatha's Soul Cauldron + Walking Ballista

Prerequisites

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

Steps

1. 1Give Sengir deathtouch, if needed.
2. 2Activate Sengir using Walking Ballista's second ability by removing a +1/+1 counter from it, dealing 1 damage to any creature an opponent controls, and killing it due to Sengir's deathtouch.
3. 3When the creature dies, Sengir's first ability triggers, putting two +1/+1 counters on it.
4. 4Repeat from step 2 as desired.

Effects

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