Vren, the Relentless

If Vren would leave the battlefield at the same time as one or more creatures an opponent controls would die, those creatures will still be exiled.

While Vren is on the battlefield, creatures your opponents control are exiled instead of dying, and abilities that trigger when a creature dies won't trigger.

Cards that would go to your opponent's graveyard for reasons other than dying, such as being discarded or milled, will still go to the graveyard and will not be exiled instead.