It is possible to a limited extent. The server doesn't send the client information on every mob in the server only the quest mob and the mobs in your vicinity (the red dots on your minimap). If you run the fullscreen hack at 1920x1080, you'll pretty much see all the mobs around you already so a hack like this wouldn't be very useful. I suppose if one didn't run fullscreen it would be nice to know if one of the red dots on the minimap is a mob their after.