Activate Ashnod's Altar by sacrificing The Master, adding {C}{C}.
When The Master dies, if it was a copy of the undying creature, its undying ability triggers, returning it from your graveyard to the battlefield as a copy of the persist creature with a +1/+1 counter on it.
Otherwise, if The Master was a copy of the persist creature, its persist ability triggers, returning it from your graveyard to the battlefield as a copy of the undying creature with a -1/-1 counter on it.
Repeat.

Infinite creature LTB

Infinite creature ETB

Infinite creature sacrifice triggers

Infinite death triggers

Infinite colorless mana

Persist Creature

Undying Creature

The Master, Formed Anew

Ashnod's Altar

Activate up to seven lands by tapping them, adding at least {2}{U}{U}{U}{B}.
Cast The Master either from your hand or from the command zone by paying {U}{B} and commander tax, if applicable, choosing to have it enter the battlefield as a copy of Palinchron.
When The Master enters the battlefield, it triggers, untapping up to seven lands.
Activate up to seven lands by tapping them, adding at least {2}{U}{U}{U}{B}.
Activate The Master by paying {2}{U}{U}, returning it to your hand from the battlefield.
Repeat from step 2.
If lands you control can tap to produce at least {3}{U}{U}{U}{B}, this combo nets infinite mana.

Infinite mana lands you control can produce

Infinite storm count

Palinchron

Activate Altar of Dementia by sacrificing The Master.
When The Master dies, its second ability triggers, returning itself from your graveyard to the battlefield as a copy of Cavalier of Night.
When The Master enters the battlefield, its first ability triggers, doing nothing.
Resolve the Altar of Dementia ability, causing target player to mill cards equal to The Master's power.
Repeat.

Infinite mill

Infinite self-mill

Cavalier of Night

Altar of Dementia

Activate Blasting Station by tapping it and sacrificing The Master.
When The Master dies, it triggers, returning itself from your graveyard to the battlefield as a copy of Driver of the Dead.
When The Master enters the battlefield, Blasting Station triggers, untapping Blasting Station.
Resolve the Blasting Station ability from step 1, dealing 1 damage to any target.
Repeat.

Driver of the Dead

Blasting Station

Activate up to five lands you control by tapping them, adding at least {U}{B}.
Cast The Master either from your hand or from the command zone by paying {U}{B} and commander tax, if applicable.
Reflections of Littjara triggers, copying the Master spell.
Resolve the copy of the Master spell, choosing to having the Master token enter the battlefield as a copy of Peregrine Drake.
When the token Master enters the battlefield, it triggers, untapping up to five lands.
Resolve the original Master spell, choosing to have it enter the battlefield as a copy of Venser.
When the nontoken Master enters the battlefield, it triggers, returning itself from the battlefield to your hand.
Repeat.

Infinite creature tokens

Infinite untap of lands you control

Reflections of Littjara

Venser, Shaper Savant

Peregrine Drake

Activate up to seven lands you control by tapping them, adding at least {U}{B}.
Cast The Master either from your hand or from the command zone by paying {U}{B} and commander tax, if applicable.
Reflections of Littjara triggers, copying the Master spell.
Resolve the copy of the Master spell, choosing to having the Master token enter the battlefield as a copy of Great Whale.
When the token Master enters the battlefield, it triggers, untapping up to seven lands.
Resolve the original Master spell, choosing to have it enter the battlefield as a copy of Venser.
When the nontoken Master enters the battlefield, it triggers, returning itself from the battlefield to your hand.
Repeat.

Great Whale

Cast The Master by paying {U}{B}.
When The Master enters the battlefield, it triggers, causing you to sacrifice Omni-Changeling and create at least two Treasure tokens.
Activate a Treasure by tapping and sacrificing it, adding {B}.
Activate The Master by paying {B} and sacrificing a Treasure, returning Omni-Changeling from your graveyard to the battlefield as a copy of The Master, which causes the Omni-Changeling to be a copy of Ruthless Technomancer.
When Omni-Changeling enters the battlefield, it triggers, causing you to sacrifice The Master and create two Treasure tokens.
Activate a Treasure by tapping and sacrificing it, adding {B}.
Activate Omni-Changeling by paying {B} and sacrificing a Treasure, returning The Master from your graveyard to the battlefield as a copy of Ruthless Technomancer.
Repeat from step 2.

Ruthless Technomancer

Training Grounds

Omni-Changeling

Activate up to two lands by tapping them, adding at least {U}{B}.
Cast The Master either from your hand or from the command zone by paying {U}{B} and commander tax, if applicable, choosing to have it enter the battlefield as a copy of Archaeomancer.
When The Master enters the battlefield, it triggers, returning Snap to your hand from your graveyard.
Cast Snap by paying {1}{U}, targeting The Master.
Swarm Intelligence triggers, copying Snap, targeting Ornithopter.
Resolve the copy of Snap, returning Ornithopter to your hand from the battlefield, and untapping up to two lands.
Activate up to two lands by tapping them, adding at least {U}{B}.
Resolve the copy of Snap, returning The Master to your hand from the battlefield, and untapping up to two lands.
Repeat.

Combos with "The Master, Formed Anew"