Ela'lothen

Got the hidden artifact appearance for Catform today after 3 screeches/moonstones; one in Feralas, one in the Hinterlands and last one in Duskwood.

Walked back through the portal I entered in Duskwood back to the Emerald Dreamway, and there was Ela'lothen. I then entered catform and used the emote /sit while targetting him, and surely - I got my Feather of the Moonspirit in bags.

Used the addon "Moonspirit" from Curse, which automatically entered waypoints when I entered the zones above when the "event" was active, showing where the moonstones could be (easy to find without however). It also does other things toward this event, and I highly recommend it.

Go into cat form, target him and /sit. You should get the item in your bags.

He spawned for me in the middle of the dreamway after getting my 3rd Stone. Loot spec was on balance and I was in balance spec. First screech was from feralas, 1 day later Hinterlands and finally today Duskwood. I have tried multiple emotes/feral abilities which do not seem to do anything. Maybe we need all stones before we can interact? Or it's locked behind rep/Artifact Knowledge? I had honored with most factions since this is just an alt. Artifact Knowledge was at 4. Hope this helps someone.