Activate Mikaeus' second ability by tapping it and removing a +1/+1 counter from it, putting two +1/+1 counters on each other creature you control.
Activate Crystalline Crawler's first ability twice by removing two +1/+1 counters from it, adding {U}{U}.
Activate Freed from the Real by paying {U}, untapping Mikaeus.
Activate Mikaeus' first ability by tapping it, putting two +1/+1 counters on it.
Activate Freed from the Real by paying {U}, untapping Mikaeus.
Repeat.

Infinite colored mana

Infinite +1/+1 counters

Mikaeus, the Lunarch

Crystalline Crawler

Freed from the Real

Lae'zel, Vlaakith's Champion

Cast Mikaeus with X=0.
Mikaeus dies due to having 0 toughness.
Luminous Broodmoth returns Mikaeus to the battlefield.
Repeat for step 2 for a mandatory loop that draws the game.

Draw the game

Infinite death triggers

Infinite ETB

Infinite LTB

Luminous Broodmoth

Solemnity

Cast Mikaeus either from your hand or from the command zone by paying {W} plus commander tax, if applicable.
Mikaeus enters the battlefield and dies as a state-based action due to having 0 toughness.
Metstatic Evangel and Magnanimous Magistrate trigger.
Resolve the Metastatic Evangel trigger, putting a reprieve counter on Magnanimous Magistrate.
Resolve the Magnanimous Magistrate trigger, removing a reprieve counter from it and returning Mikaeus from your graveyard to the battlefield.
Repeat

Infinite proliferate

Magnanimous Magistrate

Metastatic Evangel

Cast Mikaeus either from your hand or from the command zone by paying {W} plus commander tax, if applicable.
Mikaeus enters the battlefield and dies as a state-based action due to having 0 toughness.
Norn's Choirmaster and Magnanimous Magistrate trigger.
Resolve the Norn's Choirmaster trigger, putting a reprieve counter on Magnanimous Magistrate.
Resolve the Magnanimous Magistrate trigger, removing a reprieve counter from it and returning Mikaeus from your graveyard to the battlefield.
Repeat

Norn's Choirmaster

Combos with "Mikaeus, the Lunarch"