Take the charm to Candrael Twinsoul to the west of Felsoul Hold in Suramar.
She will kick you over to a Felbat, “Downfall,” defeat him and claim your new hidden skin.
Once all twelve are found, simply take them back to Archivist Inkforge for your new hidden skin! From Archivist Inkforge himself in your Order Hall.2. – Half of the item is purchased from the Valarjar Quartermaster at Exalted reputation.
Supposedly there's a chance to get three Lei Shen keys for the treasure chest scenario from Mo P on the Isle of Thunder.
Taoshi in the Rogue Order Hall can teleport you there.
– Artifact Knowledge level 4 required Once a day in the Emerald Dreamway you will have a chance to see an emote in your chat log referencing a feral screech coming from one of the portals.
Cross through that portal, look for the nearby moonstone, and touch it.