[+1]: Up to one target creature gets +2/+0 until end of turn. [–2]: Sorin deals 4 damage to any target. You gain 4 life. [–8]: Until end of turn, each Vampire you control gains "{T}: Gain control of target creature."
2019-07-12
If the chosen target is an illegal target by the time Sorin's second ability tries to resolve, the ability doesn't resolve. You won't gain 4 life.
2019-07-12
The control-change effect from ability granted by Sorin's last ability lasts indefinitely. It doesn't wear off during the cleanup step, and it doesn't expire if Sorin or a Vampire whose ability was activated leaves the battlefield. In a multiplayer game, it does expire if you leave the game.