Ugo Karlov, Prodigal Brother

Whenever Ugo Karlov, Prodigal Brother enters the battlefield or you gain control of it from another player, each opponent loses 4 life and you gain 4 life.
At the beginning of each end step, the player with the highest life total gains control of Ugo.
"By leaving his body behind my dear brother shackled himself to the Obzedat. Much as I love the Syndicate, I prefer a little more freedom."