2016-01-22 : Abilities that trigger whenever a creature an opponent controls dies won’t trigger unless that creature is a token (see below).

2016-01-22 : If Kalitas dies at the same time as creatures your opponents control, those creature cards will be exiled and you’ll get that many Zombies.

2016-01-22 : If a creature token an opponent controls dies, it goes to that player’s graveyard as normal before ceasing to exist.

2016-01-22 : You can’t sacrifice Kalitas to activate the last ability, even if it’s somehow become a Zombie.