Small creatures on live rock

[shabahang]

Today after i woke up i saw about 5 small creatures crawling on my live rock that i got from the fish store one of them had two antenna on his head and many legs the other ones had many legs and the looked very ugly

 

[shabahang]

I think one of them looked liked this

 

[mr_X]

They are most likely amphipods. They are harmless scavengers and a good addition to your tank. Don't do anything.
Edit- Just saw your pic. They are definitely amphipods.

 

[shabahang]

Thank you for your help

 

[shabahang]

I think i saw a Bristle worm too

 

[mr_X]

They are also fine to keep.

 

[shabahang]

And the other one was like a hundred legged worm

 

[mr_X]

Try to take pictures of these critters.