well the live rock come with a big brittleworm and a starfish, the question is to ID the starfish and is this brittleworm dangerous to anemone or fish?
Oh and be very careful with the worm. It is called a fireworm because if you get stuck by those bristles it will feel like your arm is on fire. Make the standard bristle worms feel petting like a fluffy puppy.
That worm actually eats corals so will the starfish. If you are doing large active fish only the star will be fine. Don't let the small size fool you they get large.