Black has always had its share of powerful cards throughout MTGs history, be it powerful Alpha cards like Dark Ritual and Demonic Tutor or more recent cards like Grief and Archon of Cruelty
(10/7/2022) In Un- games, you can put any card you own from outside the game into your hand, even if it's not part of your Draft or Sealed pool or part of your Constructed sideboard.
A myriad copy has all the characteristics of the original creature, including until end of turn abilities
The Battle of Bywater is phenomenal in tokens decks, big-butts decks (like Walls and Defender decks) and honestly just pretty good in any low to the ground kinda deck
I can see Izzet decks wanting that option
You dont know if youre going to draw the Reanimate, so you need to carefully consider if its worth discarding the Archon and exposing it to graveyard hate without knowing when the reanimation spell is coming