Effects that drain one opponent in a 1v1 game hit three opponents at a multiplayer table
Kang Prime turning nonland cards into cards with suspend could lead to some explosive turns, and Lady Loki's rules text may make your head spin for a moment, but the ability to ping and cast cards for free is not to be ignored
Out of the two split cards, Depose // Deploy does this the best
You could get some mileage out of this in artifact decks, but most often the use case will probably be reducing the cost of Goblins if you can stomach going off-tribe
Originally a mini-set, it was expanded to be a slightly larger Standard release, and yet it still has more legendary creatures than Edge of Eternities, Tarkir, and Aetherdrift combined
As I write this, Vivi is becoming a problem for Standard