Missing Mimic Tang x2
 

I have an 80g mixed reef with 3 green Chromis and a pair of clowns. About a month ago I got a small 2 1/2" mimic tang and in 4 days it disappeared (no evidence of jumping). Last Thursday I got another mimic tang (2") and today he is missing as well. I also noticed that originally I had 7 hermit crabs (all hitch hikers) and I'm down to one.
Who is the villainous hitchhiker that could be doing this? I'm thinking that maybe I have a monstor bristle star. Or maybe there's a hitchhiker killer crab (I have a few that I haven't been able to catch nor do I see them as much also. Hmmm). It couldn't be the 3 1/2" bristle worm, could it?
This is just too coincidental and how come the chromis and clowns are still around then?
Thanks for any suggestions or tips.
Cheers

Mantis maybe?? Nasty crab??

Nope, no mantis.
Nasty crab? Maybe, but he'd have to be BIG!
The tang and the 3 Chromis "sleep" within the rockwork. Chromis are still around since the very beginning. So......?