Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight, Intruder Alarm, and Kor Skyfisher

Prerequisites

• Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight on the battlefield
• Intruder Alarm on the battlefield
• Kor Skyfisher in hand

Steps

1. Cast Kor Skyfisher by paying its mana cost reduced by the number of creatures you can tap while casting it
2. When Kor Skyfisher enters, it and Intruder Alarm trigger
3. Resolve the Kor Skyfisher 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