My Favorite: Depthshaker Titan I think its a bit risky to turn all of your artifacts into 3/3s but its definitely a way to surprise everyone and close out the game when they all get melee, trample, and haste
I can hold my own against my friends most unfair decks or get revenge after being beaten into a pulp one too many games
With Urza at the helm of your deck, you can take advantage of his ability to create a 0/0 Construct creature token when he's cast, as well as tap artifacts for mana
The back face is even worse, comboing with Niv-Mizzet for an instant way to win or draw out your deck for Laboratory Maniac
Some builds include Valley Flamecaller main or side: the synergy with Hired Claw and Iridescent Vinelasher is excellent, but any extra three-drops might be stretching the curve
If you do, return the chosen cards to the battlefield tapped