Dazzling Theater // Prop Room, Intruder Alarm, and Cavern Harpy

Prerequisites

• Dazzling Theater // Prop Room on the battlefield
• Intruder Alarm on the battlefield
• Cavern Harpy in hand

Steps

1. Cast Cavern Harpy by tapping a number of creatures and paying
2. When Cavern Harpy enters the battlefield, it and Intruder Alarm trigger
3. Resolve the Cavern Harpy trigger, returning it from the battlefield to your hand
4. Resolve the Intruder Alarm trigger, untapping all creatures
5. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite storm count
• Infinite mana creatures you control can produce
• Infinite untap of creatures