ArchFiend Dragon Egg
Locations:
Price: 1,000,000 Gold
Sellback: 250,000 Gold
Rarity: Awesome Rarity
Description: This Dragon Egg seems to be pulsating ever so slightly. Given that it's got Nulgath colors, I'd hold onto it in case you can ever use it for something.
Note: Used in the 'ArchFiend Dragon Egg' quest.
Thanks to Indisturb.