Fiendlash, and Boros Reckoner

Prerequisites

• Fiendlash on the battlefield
• Boros Reckoner on the battlefield

Steps

1. Deal damage to Boros Reckoner Fiendlash and Boros Reckoner trigger
2. Resolve the Boros Reckoner trigger, dealing damage to any target Resolve the Boros Reckoner trigger, dealing at least 1 damage to itself
3. Repeat from step 2

Results

• Infinite damage