Dejimne, Void's Vagabond

Flying, Lifelink, Hexproof
{5}{w}{w}, {t}: Look through your library for up to 4 Common/Uncommon cards, or up to 3 Rare cards, or up to 2 Mythic cards, shuffle. Place non-Mythics drawn this way onto the battlefield tapped, otherwise place Mythics drawn this way into your hand. Until end of turn, all Mythics cost X less to cast, where X is the number of Mythic cards in play.

Helping goes both ways and requires cooperation. One can't help another without another needing help.