King Heredur without Bug
One could get the impression that this boss can only be killed using the bug, this is certainly not true.
First make sure you kill all other mobs around King Heredur. If the boss comes out, retreat and start killing mobs again until you are alone with King Heredur.
Then you can start killing King Heredur. When you just go and stand in front of Heredur, you'll certainly get killed. By using some tactics, things go a lot smoother. Many bosses get 'confused' when you start running around them. The program can't 'lock' an enemy and is just shooting in the wild. Just watch the video underneath where I use this tactic. Mind how Heredur uses his biggest blow just in empty space, he never really targets me. In the end I killed him with 22 hits, he only hits me twice.
For hunters and mages this would be even easier because they have a ranged attack. They don't need to come close to Heredur.