Declare Flamerush Rider, Combat Celebrant and Ghired as attackers, choosing to exert Combat Celebrant as it attacks.
Combat Celebrant, Ghired's second ability and Flamerush Rider trigger.
Resolve the Flamerush Rider trigger, creating a token copy of Combat Celebrant that is tapped and attacking.
Resolve the Ghired trigger, creating a copy of the Combat Celebrant token.
Resolve the Combat Celebrant trigger, untapping all other creatures you control and causing you to get an additional combat phase after this one.
Move to your next combat phase, and declare the Combat Celebrant token created in step 4 and Ghired as attackers, choosing to exert the Combat Celebrant token as it attacks.
Repeat from step 4.
Optionally, you may also attack with Flamerush Rider to get infinite copies of any other attacking creatures you control.

Infinite combat phases

Infinite copies of attacking creatures you control

Infinite death triggers

Infinite ETB

Infinite LTB

Infinite mana creatures you control can produce

Infinite tapped creature tokens

Infinite untap of creatures you control

Ghired, Conclave Exile

Combat Celebrant

Flamerush Rider

Samut, Tyrant Smasher

Cast Turntimber Ranger by paying {3}{G}{G}.
Turntimber Ranger enters the battlefield, creating a 2/2 Wolf creature token and putting a +1/+1 counter on Turntimber Ranger.
2/2 Wolf creature token enters the battlefield triggering Turntimber Ranger, creating a 2/2 Wolf creature token and putting a +1/+1 counter on Turntimber Ranger.
Repeat from step 2.

Combos with "Samut, Tyrant Smasher"