Overseer of the Damned, Dictate of Erebos, and Phyrexian Altar

Prerequisites

• Overseer of the Damned on the battlefield
• Dictate of Erebos on the battlefield
• Phyrexian Altar on the battlefield
• You control at least one additional creature

Steps

1. Activate Phyrexian Altar by sacrificing any other creature, adding one mana of any color
2. Dictate of Erebos triggers, causing each opponent to sacrifice a creature
3. Overseer of the Damned triggers, creating a 2/2 Zombie creature token for each creature sacrificed
4. Repeat
5. You may also repeat this loop any time a creature enters the battlefield under an opponent control

Results

• Cause each opponent to sacrifice any creature that enters the battlefield under their control
• Each opponent sacrifices all creatures they control