It all starts with the quest The Plains of Nasam, which is when you pilot a demolisher and go kill undead, available to all Horde players after completeing a few quests in the Coast of Echos. When you accept the quest and hop in one of the demolishers, you recieve a buff - although being in a vehicle you won't see it - called Siege Tank Control.

However, upon exiting the demolisher, you lose the buff immediately, so the objective here is to have the buff without being in a demolisher. These demolishers are unique in the sense that you can't re-enter them once you've exited them (you can, but they despawn), and thats how we're going to steal this buff. It may take a few tries (they are infintely respawning), but when you get in a demolisher, click the leave vehicle button then wait two or three seconds and right click the demolisher to attempt to re-enter it. If you did it right, the demolish should despawn while you are in the jumping animation to get on and you should land on your feet with the buff still on you.


Now, here's the kicker:


AS LONG AS YOU MAINTAIN THIS BUFF, NPCS CANNOT ATTACK OR EVEN TARGET YOU. However, while you are invincible from NPC attacks, you can STILL ATTACK OTHER PLAYERS.