Infinite combat damageInfinite combat phasesInfinite death triggersInfinite creature ETBInfinite creature LTBInfinite mana creatures you control can produceInfinite creature sacrifice triggersInfinite untap of creatures you control
How it works
Declare the creature with Breath of Fury attached and Sun-Blessed Guardian // Furnace-Blessed Conqueror as attackers.
Sun-Blessed Guardian // Furnace-Blessed Conqueror triggers, creating a creature token.
Deal combat damage using the creature that has Breath of Fury attached.
Breath of Fury triggers, causing you to sacrifice the creature it is attached to, then attach Breath of Fury to the creature token, then causing you to untap all creatures you control and to get an additional combat phase after this one.
Repeat each combat phase.
This loop relies on the relentless aggression of Furnace-Blessed Conqueror (the transformed back face of Sun-Blessed Guardian // Furnace-Blessed Conqueror), which uses its attack trigger to continually spawn a fresh copy of itself to catch the moving Aura. Fervor is the crucial glue that grants your entire board haste, ensuring that each newly created token can instantly join the assault during the next combat phase. Once Breath of Fury is attached to the attacking token and triggers upon dealing combat damage, you sacrifice that token to untap your creatures and slide the Aura onto the next fresh copy, creating an unstoppable chain of infinite combat phases and combat damage.