Breath of Fury, and Moira, Urborg Haunt

Prerequisites

• Breath of Fury on the battlefield
• Moira, Urborg Haunt on the battlefield
• Breath of Fury attached to any nontoken creature you control that has haste
• You control at least one additional nontoken creature that has haste
• You have a way to kill the additional creature with haste
• An opponent cannot block creatures you control
• Moira does not have summoning sickness

Steps

1. Kill the nontoken creature with haste that does not have Breath of Fury attached
2. Deal combat damage to an opponent using Moira and the creature that has Breath of Fury attached, triggering Moira and Breath of Fury
3. Resolve the Moira trigger, returning the nontoken creature with haste from your graveyard to the battlefield
4. Resolve the Breath of Fury trigger, causing you to sacrifice the creature it is attached to, then attach Breath of Fury to the other nontoken creature with haste, then causing you to untap all creatures you control and to get an additional combat phase after this one
5. Repeat from step 2 each combat phase

Results

• Infinite combat damage
• Infinite combat phases
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite mana creatures you control can produce
• Infinite sacrifice triggers
• Infinite untap of creatures you control