Endless Ranks of HYDRA is a sorcery that makes a 2/1 menacing Villain token for each opponent, and it returns to your hand whenever your commander enters or attacks so you can keep recasting it
This draws two cards if Candlekeep is in play, but also gives you two triggers from Abdel
Technomancer is the workhorse: it enters, mills three, and returns any number of artifact creatures with total mana value six or less straight to the battlefield, so one card can rebuild half a board
Most sets have a draft common common or uncommon that can repeatedly inflict one damage on each opponent just by playing other cards, like Firebrand Archer or Erebor Flamesmith
Some of these decks have excellent alternate Commander options or upgrade potential, but were squarely focused on how a deck plays out of the box, as well as how unique it is
There were also some extremely powerful cards in the set