Xathrid Demon, and Serra Avatar

Prerequisites

• Xathrid Demon on the battlefield
• Serra Avatar on the battlefield
• You have the highest life total or are tied for the highest life total

Steps

1. At the beginning of your upkeep, Xathrid Demon triggers, causing you to sacrifice Serra Avatar and causing each opponent to lose life equal to Serra Avatar's power
2. Each opponent loses the game due to having zero or less life

Results

• Each opponent loses the game
• Near-infinite lifeloss