Someone from Enrage lured Chin to Angler's for fun one day and I just happened to be there. I died 3 times! THREE. TIMES. I was pissed >_>, I hope that person got banned. >_<
Anyways! Kun Kun is really easy! And it might have immunity to elemental attacks or something but I'm a cleric and I killed it with Plume Shot so it doesn't have to be melee hits. It just has to be a skill without elemental damage (for example my whirlwind skill didn't work because it has Metal damage but the plume shot did because it's a non-elemental spell).
Have fun killing it and watch out for monsters near you. :)