Repercussion, Wrathful Red Dragon, and With Great Power...

Prerequisites

• Repercussion on the battlefield
• Wrathful Red Dragon on the battlefield
• With Great Power
• on the battlefield

Steps

1. Deal damage to Wrathful Red Dragon
2. Wrathful Red Dragon and Repercussion trigger
3. Resolve the Wrathful Red Dragon trigger, dealing damage to an applicable target
4. Resolve the Repercussion trigger, dealing damage to Wrathful Red Dragon instead of you due to With Great Power
5. Repeat from step 2

Results

• Infinite damage