Boros Reckoner, and Blazing Sunsteel

Prerequisites

• Boros Reckoner on the battlefield
• Blazing Sunsteel on the battlefield
• Blazing Sunsteel attached to Boros Reckoner
• You have a way to give Boros Reckoner indestructible
• You have a way to deal damage to Boros Reckoner

Steps

1. Give Boros Reckoner indestructible by any method
2. Deal damage to Boros Reckoner
3. Blazing Sunsteel and Boros Reckoner trigger
4. Resolve the Boros Reckoner trigger, dealing at least 1 damage to any target
5. Resolve the Blazing Sunsteel trigger, dealing at least 1 damage to Boros Reckoner
6. Repeat from step 3

Results

• Infinite damage