The Endless Sands card also gives the player many possible routes to take, and thats what we like to have in a game, although not without costs associated
Heck, I still see packs from War of the Spark hanging on the end caps at my local Walgreens
Rotation, by default, rotates several sets out of play in regular formats, meaning you can't use cards that have rotated out unless they've been reprinted
Emet-Selch, Unsundered / Hades, Sorcerer of Eld Emet-Selch, Unsundered debuted to great fanfare in the cEDH community because Hades, Sorcerer of Eld is just Yawgmoth's Will on a stick
Still, while blues history with this is all about changing costs and not much more, black has a more detailed history, which gives us clues into how WotC views different resources and their values