Jadefang

Located in Crumbling Depths, Deepholm. This rare shale spider is normally only accessible on days when the world quest Underground Economy is up. This quest is offered by Ricket, a goblin who will only appear on days when she offers a quest. She's located in the first chamber Crumbling Depths, which is situated in the enormous cave visible to the north-north-east on the Deepholm map.

Accept Ricket's quest, which gives you an explosive (but infinitely reusable) item called "Ricket's Tickers", then proceed further into the caves. Follow the first circular cave in an anticlockwise direction (watch out for the Colossal Gyreworm!) and take the second exit on the right, leaving you in a large, open cavern containing some broken pillars. Almost directly ahead you can see the side-cavern containing Jadefang, but it's up on a ledge that isn't reachable (though using Track Beasts you can confirm that Jadefang is up). Instead, turn to your right and take the eastern exit passageway, which loops back around to the left and ends at a balcony overlooking the cavern you were just in. Mount up and leap directly ahead and land on top of the broken green pillar. This places you not far from the entrance to Jadefang's cavern. Now turn your back to the entrance to Jadefang's cave and activate the "Ricket's Tickers". If all goes right, after 5-6 seconds you'll be blown backwards, up to the entrance of Jadefang's cave where you can tame it. If you miss, repeat the procedure as many times as you need, as Ricket's Tickers are reusable for as long as you have the associated quest.