Cyclonic Rift One of the most iconic staples in Commander (and also among the most groan-inducing) Cyclonic Rift manages to be one of the best board wipes in a format graced with the likes of Toxic Deluge, Farewell, and Sunfall
Vivi grows larger with every noncreature spell you cast, and its activated ability allows it to tap for mana equal to its power
This can lead to plenty of extra mill over the course of a long game, especially in Commander, where this adds each-opponent mill to any instances of single-target mill
Sakashima of a Thousand Faces and Falthis, Shadowcat Familiar Clone tribal is fun and flexible, relatively inexpensive to build, and compelling to play
Right now, there are only three near-mint listings left on TCGplayer offering 13 copies total
Edge of Eternities is a laudably weird set, and its colorless cards embrace that ethos: there's a new Eldrazi that has a pseudo-Solemn Simulacrum effect, there's a 9/9 that you can cast for three, there's a card that casts Hive Stirrings every turn, and there's a Mindslaver variant with an Emrakul-sized activation cost