The original piece certainly has its place, setting a precedent that Urza built a lot of machines that looked the same, one of which was lucky enough to become Karn
This is a cheap card, but you really dont want to play it before you have six lands so you make copies of Scute Swarm instead of the Insect tokens
Andril, Flame of the West Andril, Flame of the West gives a huge +3/+1 bonus and gets you some 1/1 Spirit tokens
A quick sidenote before we begin: the cards on this list are all-stars of the mainboard, cards which many decks want to play, and as such Ive excluded cards that primarily show up as commanders
Yahenni, Undying Partisan 7.5/10 Worse than he looks but played more than his actual power levels should dictate
Even when he was shutting down a single key card like Cryptic Command, good old Teeg was a tremendous pain since those are exactly the cards that bring down beatdown decks or open up games