Cauldron Familiar, Witch's Oven, Intruder Alarm, and Karn, Silver Golem

Prerequisites

• Cauldron Familiar on the battlefield
• Witch's Oven on the battlefield
• Intruder Alarm on the battlefield
• Karn, Silver Golem on the battlefield
• Witch's Oven does not have summoning sickness
• available

Steps

1. Activate Karn by paying , causing Witch's Oven to become an artifact creature until end of turn
2. Activate Witch's Oven by tapping it and sacrificing Cauldron Familiar, creating a Food token
3. Activate Cauldron Familiar by sacrificing a Food token, returning it from your graveyard to the battlefield
4. Cauldron Familar enters the battlefield, triggering Intruder Alarm, untapping all creatures
5. Repeat from step 2

Results

• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite mana creatures you control can produce
• Infinite sacrifice triggers
• Infinite untap of all creatures