If an equipment becomes a creature, its subject to the same rules governing creatures
Krenko benefits from you playing any of the cheap Goblins in the game even though theyre probably going to be sacrificed to Skirk Prospector or Goblin Bombardment anyways
Thopter Depths Two major combos saw play for a while in formats like Extended with the Vampire Hexmage and Dark Depths combo (giving you a 20/20 indestructible, flying Marit Lage beater on the turn you played Vampire Hexmage) or the Sword of the Meek and Thopter Foundry combo engine that made a ton of 1/1 blue Thopters
Umbris cares about your opponents' cards in exile, so you dont have to worry about most graveyard hate ruining your plan
According to that press release: Wizards of the Coast invites players and fans around the world to join in celebrating an iconic piece of gaming history with Magic: The Gathering FINAL FANTASY
Enjoy Commander Style Play in MTG Arena with Brawl While we wait for full Commander support in Arena, Brawl offers a fun and flexible way to enjoy highpowered singleton deck building