does {leyline of the Void} stop "when this creature dies" effects? Like {skullclamp}?
That depends. {Leyline of the Void} specifically says "cards", so token creatures dying will still trigger {Skullclamp}.
As for nontoken creatures, they never enter the graveyard from the battlefield with the Leyline out and so never die.
700.4 (http://imtgapp.com/forum/index.php?action=imtg;area=rule;number=700.4): The term dies means "is put into a graveyard from the battlefield."
Quote from: Dsx Cherno on March 16, 2015, 08:41:20 AM
700.4 (http://imtgapp.com/forum/index.php?action=imtg;area=rule;number=700.4): The term dies means "is put into a graveyard from the battlefield."
This is correct. {leyline of the void} will prevent all of your opponents dying effects including skullclamp except tokens since there not cards. Note that commanders don't hit the graveyard if they are being sent to the command zone when they die so they don't trigger morbid or any other dying abilities.
Edit: 8/15/2010 Leyline of the Void's second ability doesn't affect token permanents that would be put into an opponent's graveyard from the battlefield. They'll be put into that graveyard as normal (causing any applicable triggered abilities to trigger), then they'll cease to exist.
Yet another to confirm this is correct.
For comparison, look at {Rest in Peace}, which specifically says "card or token".