Urza, Lord High Artificer + Krark-Clan Ironworks + Mycosynth Golem + Mycosynth Lattice + The Cyber-Controller Combo

The Cyber-Controller in the command zone.

All other permanents on the battlefield.

The Cyber-Controller must be your commander.

You control at least two additional artifacts for each time you've cast The Cyber-Controller from the command zone this game. NOTE: This combo may fail if the opponents do not mill any creature cards

Having additional artifacts on the battlefield and/or mana available help mitigate this.

Activate Urza's first ability three times by tapping three artifacts you control, adding .

Cast The Cyber-Controller from the command zone, choosing for X to equal the amount of artifacts you control minus twice the number of times The Cyber-Controller has been cast from the command zone this game, but paying a total of due to Mycosynth Lattice and Mycosynth Golem.

When The Cyber-Controller enters the battlefield, it triggers, causing each opponent to mill X cards, and then putting all creature cards milled this way onto the battlefield face down under your control as 2/2 Cyberman artifact creatures.

Activate Urza's first ability by tapping The Cyber-Controller, adding .

Activate Krark-Clan Ironworks by sacrificing The Cyber-Controller, adding .

Choose to return The Cyber-Controller to the command zone from your graveyard.

Repeat from step 2 as able, or until each opponent has milled their library.

Significant mill