Grub, Storied Matriarch // Grub, Notorious Auntie + Combat Celebrant + Garna, the Bloodflame Combo

All permanents on the battlefield (Combat Celebrant hasn't been exerted this turn on the battlefield).

Declare Grub and Combat Celebrant as attackers, choosing to exert Combat Celebrant as it attacks. Grub and Combat Celebrant trigger.

Resolve the Grub trigger, putting a -1/-1 counter on Combat Celebrant and then creating a tapped and attacking token copy of it.

Combat Celebrant dies as a state-based action due to having 0 toughness.

Resolve the Combat Celebrant trigger, causing you to untap all other creatures you control and causing you to get an additional combat phase after this one.

Repeat each combat phase, using the Combat Celebrant token instead.

Infinite creature ETB

Infinite creature LTB

Infinite combat phases

Infinite creature tokens with haste

Infinite death triggers

Infinite mana creatures you control can produce

Infinite creature sacrifice triggers

Infinite untap of creatures you control