Repercussion, Barbed Servitor, and With Great Power...

Prerequisites

• Repercussion on the battlefield
• Barbed Servitor on the battlefield
• With Great Power
• on the battlefield

Steps

1. Deal damage to Barbed Servitor
2. Barbed Servitor and Repercussion trigger
3. Resolve the Barbed Servitor trigger, causing an opponent to lose life equal to the damage dealt
4. Resolve the Repercussion trigger, dealing damage to Barbed Servitor instead of you due to With Great Power
5. Repeat from step 2

Results

• Infinite lifeloss