Kassadin, the Void Walker

Menace, hexproof
When Kassadin, the Void Walker enters the battlefield, surveil 2.
{1}{b}: For each card put into the graveyard by surveil,
target creature gets -1/-1 until end of turn.
{3}{u}: Return Kassadin, the Void Walker to your hand.
"There are few indeed who may tread the paths between
worlds." — Kassadin, the Void Walker