Anti-Venom, Horrifying Healer, Agatha's Soul Cauldron, Walking Ballista, and Taii Wakeen, Perfect Shot

Prerequisites

• Anti-Venom, Horrifying Healer on the battlefield
• Agatha's Soul Cauldron on the battlefield
• Walking Ballista in exile
• Taii Wakeen, Perfect Shot on the battlefield
• available

Steps

1. Activate Taii Wakeen by paying and tapping it, increasing the amount of damage sources you control deal this turn by 1
2. Activate Anti-Venom using Walking Ballista's ability by removing a +1/+1 counter from it, targeting itself and putting two +1/+1 counters on it due to its replacement effect and Taii Wakeen
3. Activate Anti-Venom using Walking Ballista's ability by removing a +1/+1 counter from it, dealing 1 damage to any target
4. Repeat from step 2

Results

• Infinite damage
• Infinite +1/+1 counters on a creature