Vigor, Caradora, Heart of Alacria, and Walking Ballista

Prerequisites

• Vigor on the battlefield
• Caradora, Heart of Alacria on the battlefield
• Walking Ballista on the battlefield

Steps

1. Activate Walking Ballista by removing a +1/+1 counter on it, targeting itself, but putting two +1/+1 counters on it due to Vigor
2. Activate Walking Ballista by removing a +1/+1 counter on it, dealing 1 damage to any target
3. Repeat

Results

• Infinite damage
• Infinite +1/+1 counters