Infinite combat damageInfinite combat phasesInfinite death triggersInfinite creature ETBInfinite creature LTBInfinite mana creatures you control can produceInfinite creature sacrifice triggersInfinite untap of creatures you controlInfinite creature tokens with haste
How it works
At the beginning of your combat phase, Valduk triggers, creating at least one 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 a creature token, then causing you to untap all creatures you control and to get an additional combat phase after this one.