Intruder Alarm, and Hell's Caretaker

Prerequisites

• Intruder Alarm on the battlefield
• Hell's Caretaker on the battlefield
• Hell's Caretaker does not have summoning sickness
• It is your upkeep step
• You have at least one creature card in your graveyard and at least one additional nontoken creature on the battlefield

Steps

1. Tap Hell's Caretaker and sacrifice another creature to returning a creature in your graveyard to the battlefield
2. When that creature enters the battlefield, Intruder Alarm triggers untapping all creatures
3. Repeat

Results

• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers
• Infinite untap of creatures