All Will Be One, Opalescence, and Glistening Oil

Prerequisites

• All Will Be One on the battlefield
• Opalescence on the battlefield
• Glistening Oil on the battlefield
• You have a way to put a counter on a permanent or player
• Glistening Oil attached to All Will Be One

Steps

1. Put a counter on a permanent or player
2. All Will Be One triggers, giving an opponent a poison counter
3. Repeat step 2

Results

• Each opponent loses the game