Ok, first of all. Hello there ownedcore.
Okay, so i was doing the quest "Chains of iron" in Gorgrond when i found this.
When you get into the phased area, there are different kinds of mobs, each giving about 400-500 xp unrested. Except for 3 of the mobs, the dominated gronnling are currently giving 10-14k xp per kill if rested, so about 5-7k unrested which is alot. The good thing about this is, that if you abandon the quest and retake it, and go back, the mobs are respawned. So it's farmable.
Click here for Imgur pic of proof
Also, if this doesnt count as an exploit, im sorry x)