EntityLivingUpdateEvent is fired when an Entity is updated. If this event is canceled, the Entity does not update.

You will need to cast the event in the function header as this class:
crafttweaker.event.EntityLivingUpdateEvent
You can, of course, also import the class before and use that name then.

EntityLivingUpdateEvent implements the following interfaces and are able to call all of their methods/getters/setters as well:

• ILivingEvent
• IEventCancelable