Consider the Urza's Saga mechanic echo
Its a deck that made me fall in love with Pauper, and Ive always enjoyed making it work in other formats, especially Legacy
At X=3, this is a nine drop, and then you get three 4/4s
While theres been a bit of an ebb and flow, at this point, Im comfortable saying this Standard format has a single best deck/deck to beat. G/W Tokens has won most major Standard tournaments, including the Pro Tour and the last three Grand Prix events
Other takes on this strategy have centered on Brain in a Jar, which has the disadvantage that it can be slow to get going late, but its advantage, in addition to not being an enchantment, is that it has an interesting combination with Days Undoing that allows you to cast Days Undoing on your opponents turn, skipping the end the turn clause, which means that the Days Undoing ends up in your graveyard
Before we get to the cards, lets review a couple of concepts