The Cyber-Controller | Urza, Lord High Artificer | Krark-Clan Ironworks

(and two other cards)

The Cyber-Controller in the command zone.
All other permanents on the battlefield.
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 ({3} magic symbol) .
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 ({3} magic symbol) 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 ({1} magic symbol) .
Activate
Krark-Clan Ironworks by sacrificing
The Cyber-Controller, adding ({C} magic symbol) ({C} magic symbol) .
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.