You will need: A better weapons to fight aggro's that has high weapon skill / any level 65+ (the place is in SMV)
Ok so what you do is you go to SMV and go to the location of the corruptors of [element]. Just search Corruptor of on thottbot and it will come up with all four mob names.
Once you do that, all you need to do is have the weapon that you want skilled up equiped and another weapon ready. Then all you need to do is attack those mobs that has the shield around it (when I say that I mean like a water thing around the mob) and it needs to have totems shooting stuff at them. Then all you need to do is attack the mob with all the things I listed and then just attack and watch your computer (due to mobs around them, they will attack you once in a while) If you are a hunter then just keep your pet on defensive and have them attack the mob that is attacking you. (If the mob that gives wep skill says immune whenever you attack it DOES NOT MEAN it doesn't give weapon skill. It means that it will not attack you/it is immune to damage. Once you kill the totems is when he attacks you. :icon_headbang: Just trying to get AWAY from leecher.