Breath of Fury attached to any nontoken creature you control that has haste.
You control at least one additional nontoken creature that has haste.
You have a way to kill the additional creature with haste.
An opponent cannot block creatures you control.
Moira does not have summoning sickness.
Steps
Kill the nontoken creature with haste that does not have
Breath of Fury attached.
Deal combat damage to an opponent using
Moira and the creature that has
Breath of Fury attached, triggering
Moira and
Breath of Fury.
Resolve the
Moira trigger, returning the nontoken creature with haste from your graveyard to the battlefield.
Resolve the
Breath of Fury trigger, causing you to sacrifice the creature it is attached to, then attach
Breath of Fury to the other nontoken creature with haste, then causing you to untap all creatures you control and to get an additional combat phase after this one.
Repeat from step 2 each combat phase.
Results
Infinite combat damage.
Infinite combat phases.
Infinite death triggers.
Infinite creature ETB.
Infinite creature LTB.
Infinite mana creatures you control can produce.
Infinite creature sacrifice triggers.
Infinite untap of creatures you control.
Metadata
Bracket tag
SpicyBracket 3-4+
Probably 3 or 4, but hard to classify
1
2
3
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5
1 · Exhibition5 · cEDH
Bracket tags are estimated from the cards and results of each combo, as a guideline rather than a strict classification.