Black Brittle Starfish Question

[Madreefer]

I figured out what it is. The lawnmower blenny that has turned in to a real A hole in the last few months has been biting at it alot and has decided to take over the hole that the starfish lives in. Not only that but he is also attacking a clam and now the clam has detached from the rock he has been on for the last few years.