Heidar, Rimewind Master, Intruder Alarm, Dual Nature, Ashnod's Altar, and Crookshank Kobolds

Prerequisites

• Heidar, Rimewind Master on the battlefield
• Intruder Alarm on the battlefield
• Dual Nature on the battlefield
• Ashnod's Altar on the battlefield
• Crookshank Kobolds in hand
• Heidar does not have summoning sickness
• You control at least four snow permanents

Steps

1. Cast Crookshank Kobolds by paying
2. When Crookshank Kobolds enters the battlefield, Intruder Alarm and Dual Nature's first ability triggers
3. Resolve the Intruder Alarm trigger, untapping all creatures
4. Resolve the Dual Nature trigger, creating a token copy of Crookshank Kobolds
5. Activate Ashnod's Altar by sacrificing the Crookshank Kobolds token, adding
6. Activate Heidar by paying and tapping it, returning Crookshank Kobolds to your hand from the battlefield
7. Dual Nature's second ability triggers, exiling nothing
8. Repeat

Results

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