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.

Infinite combat phases

Infinite creature tokens

Infinite ETB

The Master, Multiplied

Legion Loyalty

Combat Celebrant

Cybermen Squadron

Biotransference

At the beginning of your combat phase, Duke Ulder triggers, giving a Bloodthirster haste and myriad until end of turn.
Declare the Bloodthirster targeted in step 1 as an attacker.
The Bloodthirster's myriad ability triggers, creating a token copy of it tapped and attacking each other opponent.
Deal combat damage to an opponent using a Bloodthirster token, triggering the token, untapping it and causing you to get an additional combat phase after this one.
Move to your next combat phase. You will not exile the Bloodthirster tokens due to The Master.
Repeat.

Infinite creature tokens with haste

Infinite combat damage

Bloodthirster

Duke Ulder Ravengard

Mycosynth Lattice

Activate Liquimetal Torque's second ability by tapping it, causing Lunar Force to become an artifact until end of turn.
At the beginning of your combat phase, Mishra triggers, creating a token copy of Lunar Force that is a 4/4 artifact creature named Mishra's Warform in addition to its other types.
At the beginning of your end step, Mishra's Warform triggers, causing you to fail to sacrifice Mishra's Warform due to The Master.
Whenever an opponent casts a spell, Mishra's Warform triggers, countering that spell and causing you to fail to sacrifice it due to The Master.
Repeat step 4 as necessary.

Counter all spells opponents cast

Mishra, Eminent One

Lunar Force

Liquimetal Torque

Encroaching Mycosynth

Activate Liquimetal Torque's second ability by tapping it, causing Hesitation to become an artifact until end of turn.
At the beginning of your combat phase, Mishra triggers, creating a token copy of Hesitation that is a 4/4 artifact creature named Mishra's Warform in addition to its other types.
At the beginning of your end step, Mishra's Warform triggers, causing you to fail to sacrifice Mishra's Warform due to The Master.
Whenever a player casts a spell, Mishra's Warform triggers, countering that spell and causing you to fail to sacrifice it due to The Master.
Repeat step 4 as necessary.

Counter all spells

Hesitation

Activate Liquimetal Coating by tapping it, causing Lunar Force to become an artifact until end of turn.
At the beginning of your combat phase, Mishra triggers, creating a token copy of Lunar Force that is a 4/4 artifact creature named Mishra's Warform in addition to its other types.
At the beginning of your end step, Mishra's Warform triggers, causing you to fail to sacrifice Mishra's Warform due to The Master.
Whenever an opponent casts a spell, Mishra's Warform triggers, countering that spell and causing you to fail to sacrifice it due to The Master.
Repeat step 4 as necessary.

Liquimetal Coating

Cast Omarthis by paying {2}.
Echoes of Eternity triggers, copying the Omarthis spell.
Resolve the copy of the Omarthis spell, creating a token copy of Omarthis with one +1/+1 counter on it.
Resolve the original Omarthis spell, causing it to enter the battlefield with one +1/+1 counter on it.
The token Omarthis's first ability triggers twice.
Resolve the first trigger, putting a +1/+1 counter on the token Omarthis.
The nontoken Omarthis's first ability triggers twice.
Resolve the first trigger, putting a +1/+1 counter on the nontoken Omarthis.
Repeat from step 5.

Infinite +1/+1 counters on a creature token

Infinite +1/+1 counters on Omarthis

Omarthis, Ghostfire Initiate

Echoes of Eternity

Cast Time Stretch by paying {8}{U}{U}, causing you to take two extra turns after this one.
Activate Kiki-Jiki by tapping it, creating a token copy of Izzet Chemister.
Activate the Izzet Chemister token's first ability by paying {R} and tapping it, exiling Time Stretch from your graveyard.
At the beginning of your end step, Kiki-Jiki triggers, but you cannot sacrifice the Izzet Chemister token due to The Master.
On your next turn, activate the Izzet Chemister token's last ability by paying {1}{R}, tapping it, and sacrificing it, casting the exiled spell without paying its mana cost.
Resolve that spell, causing you to take two extra turns after this one.
Repeat from step 2 (note that you can divide these steps among your multiple extra turns to reduce the minimum mana required to the amount shown in the prerequisites).

Infinite turns

Kiki-Jiki, Mirror Breaker

Izzet Chemister

Time Stretch

Activate Liquimetal Coating by tapping it, causing Hesitation to become an artifact until end of turn.
At the beginning of your combat phase, Mishra triggers, creating a token copy of Hesitation that is a 4/4 artifact creature named Mishra's Warform in addition to its other types.
At the beginning of your end step, Mishra's Warform triggers, causing you to fail to sacrifice Mishra's Warform due to The Master.
Whenever a player casts a spell, Mishra's Warform triggers, countering that spell and causing you to fail to sacrifice it due to The Master.
Repeat step 4 as necessary.

Cast Replication Technique by paying {4}{U}, creating a token copy of Dark Depths.
Activate Mishra's Groundbreaker by tapping and sacrificing it, causing Dark Depths to become a creature.
Activate Vampire Hexmage by sacrificing it, removing all counters from the Dark Depths token.
The Dark Depths token triggers, causing you to not sacrifice it due to The Master.
Step 4 repeats infinitely, creating a mandatory infinite loop, causing the game to end in a draw.

Draw the game

Dark Depths

Vampire Hexmage

Mishra's Groundbreaker

Replication Technique

Declare Satya as an attacker.
Satya triggers, creating a tapped and attacking token copy of Medomai the Ageless, and causing you to get {E}{E}.
Deal combat damage using the Medomai the Ageless token.
The Medomai the Ageless token triggers, causing you to take an extra turn after this one.
At the beginning of your end step, Satya triggers, causing you not to sacrifice the Medomai the Ageless token due to The Master.
Repeat each turn.

Satya, Aetherflux Genius

Medomai the Ageless

Activate Kaya's third loyalty ability by removing three loyalty counters from it, exiling Lunar Force and creating a token copy of it that is a 1/1 Spirit in addition to its other types.
Whenever an opponent casts a spell, the Lunar Force token triggers, countering that spell and causing you to fail to sacrifice it due to The Master.
Repeat step 2 as necessary.

Kaya, Intangible Slayer

Activate Kaya's third loyalty ability by removing three loyalty counters from it, exiling Hesitation and creating a token copy of it that is a 1/1 Spirit in addition to its other types.
Whenever a player casts a spell, the Hesitation token triggers, countering that spell and causing you to fail to sacrifice it due to The Master.
Repeat step 2 as necessary.

Combos with "The Master, Multiplied"