How can I tell if my "choc. chip" starfish is dead in my saltwater aquarium?

Where are his eyes? Granted, one of my humbugs tried to bite off a tenticle, however, he was not successful in his attempt to attack. "Patrick" (starfish's name") held his own. Patrick looks fine, but the way I understand it, if he dies, he'll look just fine petrified as well. Should Patrick be moving alot?