Heliod, Sun-Crowned, and Walking Ballista

Prerequisites

• Heliod, Sun-Crowned on the battlefield
• Walking Ballista on the battlefield
• Walking Ballista has at least two +1/+1 counters on it
• available

Steps

1. Activate Heliod by paying , giving Walking Ballista lifelink until end of turn
2. Activate Walking Ballista's second ability by removing a +1/+1 counter, dealing 1 damage to any target
3. Walking Ballista's lifelink triggers, causing you to gain 1 life
4. Heliod triggers, putting a +1/+! counter on Walking Ballista
5. Repeat from step 2

Results

• Infinite damage
• Infinite lifegain
• Infinite lifegain triggers