Blazing Sunsteel, and Metropolis Reformer

Prerequisites

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

Steps

1. Give Metropolis Reformer indestructible, and then deal damage to Metropolis Reformer
2. Metropolis Reformer and Blazing Sunsteel trigger
3. Resolve the Metropolis Reformer trigger, causing you to gain life equal to the damage dealt
4. Resolve the Blazing Sunsteel trigger, dealing that much damage to Metropolis Reformer
5. Repeat from step 2

Results

• Infinite lifegain
• Infinite lifegain triggers