The Master, Multiplied | Cybermen Squadron | Encroaching Mycosynth

(and one other card)

Declare
Combat Celebrant as an attacker, choosing to exert it as it attacks.
Combat Celebrant's myriad and printed abilities trigger.
Resolve the myriad trigger, creating a token copy of
Combat Celebrant attacking each other opponent.
Resolve the second trigger, causing you to untap all other creatures you control and to get an additional combat phase after this one.
Move to your next combat phase, not exiling the
Combat Celebrant tokens due to
The Master.
Repeat using a
Combat Celebrant token that hasn't attacked this turn.