Restless Shadeling

Restless Shadeling does in fact rest.

Found in the Master's Cellar in the ruined village, to the immediate south of Karazhan.

Resltess Shadeling can only be found in the early morning, from 12am - 7am EST

I find the H/S version most useful, but I am partial to dodge moves. With Arcane Blast you can handle fliers quite well. Plagued Blood is very useful in multi attack teams or with Turret or Immolation pets. I use it a bit but rarely see it in use by others. Guess it is not as obviously powerful as some of the other Undead pets.

Not a lot of the comments I've seen mention where they are found when they spawn. You will not see any above ground, they will be in the cellars of the little ruined houses in front of the main Kara entrance(there are 2). I sat around for 20 mins waiting for Midnight, and as soon as it hit, a whole bunch of them appeared on my minimap. The nice thing was that there was only a Pally from CRZ and myself hunting for these little guys, and I'm more than certain both of us walked away with a rare.

There are two areas of Master's Celler where this thing spawns.  One stairway leads to an actual celler where only a few spawn.  Then there is another stairway nearby that leads into a winding cavern where around 15 more spawn.  Both areas are considered "Master's Celler".  Uncommon versions = 1038 health while rare versions = 1100+ health.  It's an easy way to pickup a 16 pet because you only fight the Shadeling, no other pets join the fight against you.

For people who are looking for this guy as of recently of me posting this comment, you will notice alot spawn behind a wall of fel that you  cant get past so what you have to do is do a bit of quests for the guys standing near karazhan and it will open up the fell wall on the quest that has you disguise as demon or somthing. Hopefully this is helpful for new pet collectors :D

This is an awesome pet vs. Tarr the Terrible. With some good luck this pet can easily solo him. Mine has speed 273.  Always start with Phase Shift, then Plagued Blood for damage & heals, then spam Shadow Shock til 1st pet is dead.  Then repeat on 2nd pet, until 2nd pet is dead.  On 3rd pet, Phase Shift & Plague, he will soar above you and be unattackable for one round, bring your Elekk Plushie in now, or a pet you want to level up. Your 3rd pet is backup.

Was going a little crazy trying to find this guy. The pet is underground of Kara, there's little stairs all around the villages. They don't all lead to the same place and there's not a pet in each underground area. The first one I went in by Kara's entrance didn't have any however the other entrance did. Of course the first one I found I killed in sheer excitement >.< Found it at 8:58 am server/local time. 

Just got mine today! Just for East Coast people it doesnt matter if its 12am server time and your on an east coast server you must stay up til 3am to hit midnight west coast  server time. I dont know if this was mentioned really sucked staying up for it but after the fifth battle I got my rare!

I can confirm that these are still available in game under BfA. I logged on this morning at 1201 server time and there were at least 15 that had spawned at the Masters Cellar. First one I battled was a uncommon H/S and defeated him. Second one was a rare H/H and got that also. It was the last pet I needed for the Eastern Kingdoms Safari and World Safari. 

It's 20 min past midnight server time on area52 and haven't seen any on either side of the cellar. The spawn time is NOT based on server time. It is specifically 12am pacific standard time. so it will be 1:30 mountain, 2am cst and 3 am eastern. These spawn during the availability window and respawn after catching/defeating in battle. Combat killing wasn't necessary. I got a rare H/H after 8 attempts and a rare H/S on the way out of the cavernous area near where I caught a common earlier.

I've been checking the area of a few days and only today saw them spawning.  I checked at just past 7am GMT and saw a few: mostly Poor and Common, but one Uncommon which I caught and am very happy with!

Great morning, in fact - got Terky just before as well. :)

I'm on the Ysera server - and the Restless Shadelings did not spawn until 3am server time. When they finally did spawn, it was all at once. Just a heads up for others on my sever. 

I've been coming back to this location every now and then hoping to happen upon the Restless Shadeling, not realizing that they only appear in early morning. Well, here I am on a late night and sure enough, 4:45a server time, it's flooded with them. Unfortunately for me there was another player there following me around and killing them off. I managed to get a poor quality - better than nothing! 

From what I've seen, these guys start spawning at midnight, but on Pacific time, not your server's time. I'm not sure if this also applies to non-American servers.

As for the pet itself, I'd recommend a H/H build. Phase Shift will be less useful, but the Shadeling looks like it gets outran a lot even with H/S, so it might be best to shoot for the extra turn the Undead racial gets for being slower, and use it to get off one last Plagued Blood for the rest of your team.

Finally spawned after a month of checking.  I found them @ 3 AM servertime, were still up @ 3:25.  

As a note, they appear rather abundently in both the wine and cave sides of the cellar and they can be detected above ground, so don't waste time sitting or walking down into the caves, just fly over the area to check if they're up. 

Lastly, I was the only one in the zone, so I was able to check all but 2 that spawned, (accidently killed).  Found 1 rare and 2 uncommons.

9.00am realm time is the switch over point. I was there today and all despawned at exactly this time.

Based on comments looked for a cave nearby found one with ogres but no shadelings so flew around and found 2 opening near the raid and found a few. Look for cellar openings at 48.24, 78.31.

update: found a spawn of 6 or more in one cellar but then after an hour no more had spawned so I was pretty aggravated with blizzard. Finally 2 more spawned and the elusive rare was the last one I battled and I got him! woot

just got here at 230am EST. No shadlings underground but a TON of arcane eyes up top. Follow up post when and if I find me a shadling

update: 3:01 EST SPAWN CITY! They will all spawn 1 minute after midnight PST! Got my rare after about 9 attempts.