Modern Esper Urza by Archaeusdota
This Esper-colored take on Urza is structured in a way to utilize Mox Amber for the explosive power that Mox Opal used to offer. As such, one of the key cards is Emry, Lurker of the Loch, which can be powered out for one mana quite easily and then enables big turns with Mox Amber. An uncontested Emry will typically result in a win after you can play two or three artifacts from the graveyard for free. The great thing, however, is that even if Emry gets killed, your graveyard will still be stocked for future use with Lurrus of the Dream-Den, the Thopter Foundry/Sword of the Meek combo or another copy of Emry.
The Thopter Foundry plus Sword of the Meek combo is the most direct route to victory. With both cards in play, you sacrifice Sword of the Meek to gain a life and make a 1/1 Thopter, which returns Sword of the Meek to the battlefield and allows you to repeat the process. In this way, you can generate a number of tokens and an amount of life equal to the amount of mana you invest (you can do this across a number of turns, mind you). This is already extremely good against any opponent who’s looking to pressure your life total or attack with creatures. However, if you have the Lord High Artificer, your Sword of the Meek also generates one mana each time around, meaning that you can repeat the process infinitely.
Sword of the Meek is a particularly nefarious combo piece because even if it gets milled or destroyed, it still works! You simply sacrifice any other artifact to make a Thopter, which returns Sword from your graveyard and starts the combo up. Since it’s an Equipment, you can search for your one copy via Stoneforge Mystic with minimal risk of drawing a card that might be weak in your opening hand.
Therein lies the beauty of Esper Urza. Stoneforge Mystic is simply an awesome card, which can score you easy wins via turn three Batterskull if it goes unanswered. This deck scores high marks on both synergy and individual card quality, meaning you’ll have an impressive amount of consistency and control over the direction of the game.