I absolutely adore foreshadowing, especially if it's subtle and doesn't truly hit someone until after something big has happened. I love dropping little hints here and there about what may occur in the future - though as others have said it only really works when you're interacting with the same individual or bunch of role-players on a regular basis.
FFXIV uses it quite often to tell a good story - especially in Heavensward.
FFXIV uses it quite often to tell a good story - especially in Heavensward.