I am sure many people are aware of this... but for those that aren't - here is a lil level helper
There are some LT. and Boss mobs that dont fight back in certain situations. I have noitced this with the following mobs under the stated conditions. We should get a running list of these types of mobs.
Button Man Muscle - these guys don't attack when there are no other botton men, or capo gunners in there group.
Telsa Knight - Won't attack when you hit the group and they are holding steel bars.
... I am sure there are other mobs suffering this glitch. Please list them here so we can benenfit