The bottom half of the mythics from Masters 25 are horrible from a value perspective, and it's hard to imaging too many players happily cracking Tree of Redemption or Prossh, Skyraider of Kher
The Darkness Crystal instead screws up your opponents graveyard shenanigans and otherwise steals their cards from exile
Common strategies like wheels appreciate this card very much, and for once, you can play this in something like mono-blue, a color that usually doesnt have this kind of reach
One card might not seem like a huge difference, but one card is often all it takes to win a game of Magic
Nicol Bolas is expensive, but it has a very strong effect when it hits another player
My personal favorites are Sporemound and Life and Limb