I noticed that the assassin's grapple is more touchier (you have to be really close, etc..). But when i use any other class, the grapple seems to be easier to use. Maybe its just me, but i notice the small things.
Could be touchier. I mean, if it's suppose to stronger from the back than a regular grapple then they might make it a bit harder to pull off. Gotta work to get that prokill.
