Cast Moritte of the Frost from your hand or from the command zone by paying {2}{G}{U}{U} plus commander tax, if applicable, choosing to have it enter the battlefield as a copy of Staff of Eden.
Put Moritte of the Frost into your graveyard due to the legend rule.
Morrite of the Frost's enters-the-battlefield ability and Simulacrum Synthesizer's second ability trigger.
Resolve the Simulacrum Synthesizer trigger, creating a 0/0 Construct artifact creature token.
Resolve the Moritte of the Frost trigger, returning Moritte of the Frost from your graveyard to the battlefield as a copy of Staff of Eden.
Repeat from step 2.

Infinite ETB

Infinite creature tokens

Infinitely large Construct tokens

Moritte of the Frost

Staff of Eden, Vault's Key

Simulacrum Synthesizer

Cast Mycosynth Lattice by paying {6}.
When Mycosynth Lattice enters the battlefield, Simulacrum Synthesizer's second ability triggers, creating a 0/0 Contruct artifact creature token that enters the battlefield as a copy of Essence of the Wild.
When the Essence of the Wild token enters the battlefield as an artifact due to Mycosynth Lattice, Simulacrum Synthesizer's second ability triggers, creating a 0/0 Contruct artifact creature token that enters the battlefield as a copy of Essence of the Wild.
Repeat step 3.

Combos with "Simulacrum Synthesizer"