Defiling Daemogoth, and Serra Avatar

Prerequisites

• Defiling Daemogoth on the battlefield
• Serra Avatar on the battlefield

Steps

1. Deal combat damage using Serra Avatar, doubling your life total due to its lifelink
2. At the beginning of your end step, Defiling Daemogoth triggers, causing each opponent to lose life equal to the life you've lost this turn

Results

• Near-infinite lifegain
• Near-infinite lifeloss