You may activate the first ability even if you control no creatures. Sarkhan Vol gains a loyalty counter, but the ability will have no effect.
2008-10-01
Sarkhan Vol’s first ability affects only creatures you control when that ability resolves.
2008-10-01
You may target any creature with the second ability, not just a creature an opponent controls. If you target a creature you already control, you’ll gain control of it (which will usually have no visible effect), it’ll untap, and it’ll gain haste until end of turn.
+1: Creatures you control get +1/+1 and gain haste until end of turn.
−2: Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.
−6: Create five 4/4 red Dragon creature tokens with flying.
