I was with my friend, and our bloodstalkers did thousands of damage, at least 13,000, to a normal creature. But, when we fought an X rock elemental, it only did about 950 damage points. So I say, just run.
If you are unsure if a rock is a disguised golem or not, a spyglass shows their name and level even when disguised. Also, when disguised, the rocks often move slightly as you get close, re settling onto the terrain.