Syncs tentacle health and players in stomach within raid during C'thun encounter. Players outside the stomach can only see stomach tentacle health if players inside the stomach have the WA and vice versa.
DBM incorporated similar functionality into the base C'thun mod. If your raid uses DBM, you probably don't have a huge need for this aura anymore. My selfish and biased opinion is that this still works/looks better, but do what ya want! :)