Thornbite Staff, Heavy Arbalest, and Gorgon's Head

Prerequisites

• Thornbite Staff on the battlefield
• Heavy Arbalest on the battlefield
• Gorgon's Head on the battlefield

Steps

1. Activate the creature by tapping it, dealing damage to an opponent's creature
2. The opponent's creature dies due to deathtouch, triggering the second ability granted by Thornbite Staff, untapping your creature
3. Repeat until all opponents' creatures die
4. Repeat each time a creature enters the battlefield under an opponent's control

Results

• Destroy all creatures opponents control
• Destroy all creatures opponents control whenever a creature enters the battlefield