Morbid is an new ability word introduced in Innistrad. Ability words used to connect abilities but without putting specific rules that govern the ability in the comprehensive rules. Everything you need to know about how Morbid works appears on each card.
Morbid abilities can be static, triggered or activated and they can continuous, one-shot or replacement effects. There is no one thing that morbid abilities can do. The connection between all of these abilities is that they all ‘care’ if a creature has died sometime previously that turn. If a creature has died that turn, then the Morbid ability applies. As mentioned above this can mean several things. Here are some examples of Morbid cards and what type of ability and effect they have:
Caravan Vigil has a static morbid ability that generates a replacement effect when it is applied.
The morbid ability of Hollowhenge Scavenger is a triggered ability that generates a one shot effect when it resolves.
Another morbid triggered ability would be Morkrut Banshee, however this ability generates a continuous effect.
Finally, the ability of Skirsdag High Priest is an activated ability with a morbid restriction, in other words you can’t activate the ability unless a creature has died that turn. This ability generates a one-shot effect.