Seam Rip + Portable Hole Seam Rip is an exceptionally cheap riff on Oblivion Ring
And just in case you thought it couldn't get any worse, he lists "5" as an example of a Mersenne prime, which
To activate the cards and issue damage to their nearby foes, players discard a card, activating up to three placed elementals of the same type or number of the discarded card
We went through various versions, but here's what we handed off from vision design: Afraid (If an enchantment, Horror, or Nightmare you control entered the battlefield or attacked this turn, all opponents are afraid.) This version interacted not just with enchantments, but a few of the creatures we felt most embodied the genre, Horrors and Nightmares
While we had designed individual cards that made temporary tokens, myriad was the first named mechanic to make use of this design technology