Vrock

Void — At the beginning of your end step, if a nonland permanent left the battlefield this turn or a spell was warped this turn, you draw a card and lose 1 life.

Flying (This creature can't be blocked except by creatures with flying or reach.)

At the beginning of your end step, if an opponent lost life this turn, put a +1/+1 counter on this creature and draw a card. (Damage causes loss of life.)

At the beginning of each player's end step, if no permanents left the battlefield this turn, that player loses X life, where X is Sarevok's power.

Choose a Background (You can have a Background as a second commander.)

Flying

At the beginning of each opponent's end step, that player chooses up to two creatures they control, then sacrifices the rest.

At the beginning of each end step, if a creature dealt damage by this creature this turn died, put that card onto the battlefield under your control. Sacrifice it when you lose control of this creature.

Flying

Disappear — At the beginning of your end step, if a permanent left the battlefield under your control this turn, create a 1/1 black Insect Warrior creature token with flying.

, Sacrifice a token: Draw a card.