Bristle worms, can they go foe, an attempt to stay alive?

I know we do like them. I love them, I see em as tooth brushes for our rock work. But. If underfed do you guys think they would go for other seseptible creaters such as serpent stars around their size (star is about 3-4in from leg to leg and the biggest bristle worm I saw tonight was around 4in, thin but long)? I'm lookin for my serpent star tonight, I can't find him in a 10g tank. I know he is hungry, I've blown a syringe of food into the tank for the past 3 days after not feeding him for 5 days nor the tank (only zoa's, a baby hammerhead and a baby frogspawn with 2 colonies of zoa's, a colony of paly's and a few sponges in the tank) the rock work vrs his size would def allow me to see him when I feed, either I didn't feed him enough and he died or the bristle worms got him cuz their hungry. Tonight I saw 4 bristles come out when I fed, all thin but ranging from 2-4in. What do you guys think? And yes, I'll be relocating at least half to my 55g DT