The sheer volume of cards demands a way to store cards that maximizes the space available, and card boxes do that
In an artifact-heavy deck with cards like Treasure Map or Servo Exhibition, Sami helps cast huge haymakers like Aurelia's Fury or Hellkite Igniter way ahead of curve
You could force something to block Nemesis, or cycle a Jund Sojourners, or sacrifice a Goblin Arsonist
My goal was to have players to find their favorite classic job, put that Equipment into their deck, and grant that job to their favorite creatures (what if Cloud were a dragoon?) or double down on the same flavor (I equip Kain with Dragoon's Lance!)
(Artifacts, legendaries, and Sagas are historic.) Land Path of Ancestry This land enters tapped
Blood Artist The only downside of Blood Artist in the EDH era is that it targets a single opponent on each trigger