Sean, Game Master

Banding, Hexproof, Protection from Gamers
When Sean, Game Master enters the battlefield,
if a player named Sean is currently playing,
they merge their life total and library with yours
and become your teammate. (Your permanents,
graveyards, hands and libraries are reshuffled
into a new library, and you draw a new hand of seven
cards. Choose any number of cards in your hand
or on top of your library. Those cards become your
teammate's hand and library, respectively.)