Agatha's Soul Cauldron, Fiendish Panda, and Walking Ballista

Prerequisites

• Agatha's Soul Cauldron on the battlefield
• Fiendish Panda on the battlefield
• Walking Ballista in exile

Steps

1. Activate Fiendish Panda by using Walking Ballista's ability by removing a +1/+1 counter from it, dealing 1 damage to any target and causing you to gain 1 life due to its lifelink
2. Fiendish Panda triggers, putting a +1/+1 counter on it
3. Repeat

Results

• Infinite damage
• Infinite lifegain triggers
• Infinite lifegain