Breath of Fury, Sharding Sphinx, and Urabrask the Hidden

Prerequisites

• Breath of Fury on the battlefield
• Sharding Sphinx on the battlefield
• Urabrask the Hidden on the battlefield
• Breath of Fury attached to another artifact creature you control
• An opponent cannot block creatures you control

Steps

1. Deal combat damage to an opponent using the creature with Breath of Fury attached, triggering Breath of Fury and Sharding Sphinx
2. Resolve the Sharding Sphinx trigger, creating a 1/1 Thopter artifact creature token
3. Resolve the Breath of Fury trigger, causing you to sacrifice the creature it is attached to, then attach Breath of Fury to the Thopter token, then causing you to untap all creatures you control and to get an additional combat phase after this one
4. Repeat 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