Breath of Fury, We Ride at Dawn, and Concordant Crossroads

Prerequisites

• Breath of Fury on the battlefield
• We Ride at Dawn on the battlefield
• Concordant Crossroads on the battlefield
• Your commander is on the battlefield
• Breath of Fury attached to any creature that isn't your commander
• An opponent cannot block creatures you control

Steps

1. Declare your commander and the creature with Breath of Fury attached as attackers
2. We Ride at Dawn's second ability triggers, creating a 1/1 Mercenary creature token
3. Deal combat damage using the creature that has Breath of Fury attached
4. Breath of Fury triggers, causing you to sacrifice the creature it is attached to, then attach Breath of Fury to the Mercenary token, then causing you to untap all creatures you control and to get an additional combat phase after this one
5. 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