They both buff the same type of creatures (and Blex's itself a Pest), plus the obvious lifegain synergy
If the matchup is not a race, you can also side out some number of Narcomoeba or Bloodghast
This is a new mechanic debuting in Innistrad: Crimson Vow that allows you to pay an alternate cost for the card in order to become an editor and gain a version of the card that is the same, but you have to remove the words in the brackets
Shrinking opposing boards while you boost your own creatures often wipes out small armies on entry, and if it sticks around, it quickly turns combat into a one-sided affair
Its one of the few times Ive actually bothered sticking with Standard for more than just a dabble in the last year
It gains percentage points against Abzan and Grixis Control while not losing too much against its good matchups like Affinity, Amulet Bloom, and G/R Tron