1 Phyrexian Rebirth
(Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.) Search your library for a card, put it into your hand, then shuffle
This being said, opening Counterspells, Brainstorms, and Relentless Rats at a rate of more than two per box (on average) is a nice bonus for players and helps make sure you come away with a little something even when your rares and mythics are poor
Mushu, Your Worst Nightmare, giving one of your characters Rush, Reckless, and Evasive means you're able to send a tank in to wreak havoc and send your opponents' characters to the discard
A 1/4 merfolk wizard for three mana, Araumi can be tapped, exiling a number of cards in its controller's graveyards equal to the number of opponents they have