Unhatched Jubling Egg

Unhatched Jubling Egg is a unique item. After a week in the player's possesion, the item can be used, at which point the egg 'hatches' and becomes

Source
The item can be obtained after completing the quest Spawn of Jubjub. Note that this quest is both accepted and turned in at the Darkmoon Faire, which visits Elwynn Forest, Mulgore and Shattrath City periodically.