Breath of Fury + Urabrask the Hidden + Seraphic Steed
Breath of Fury
Urabrask the Hidden
Seraphic Steed
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 Seraphic Steed as attackers.
Seraphic Steed 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 brilliant sequence hinges on the recursive potential of Breath of Fury, which sacrifices its host upon dealing combat damage to a player and jumps to a new creature to grant an extra combat phase and untap your board. To make this loop self-sustaining, Seraphic Steed steps in to provide a fresh target each time by generating a 3/3 white Angel creature token whenever it attacks while saddled. Meanwhile, Urabrask the Hidden ensures your freshly untapped creatures and newly minted tokens can immediately join the fray by granting them haste, closing the loop into an infinite succession of combat phases.