Blizzard released a news post previewing the new zone coming in Patch 10.1, Zaralek Cavern!
Muster your courage as you continue your adventure through the Dragon Isles and pursue your enemies into the dangers of the Zaralek Cavern. Along the way, dive deeper into the mysteries of the Black Dragonflight, meet new allies and foes, discover treasures and rewards, and more.To reach Zaralek Cavern, complete the “Embers of Neltharion” campaign that will put you onto the path which guides you down beneath the Dragon Isles and into a vast underground world. Entrances to Zaralek Cavern lie within the chasm between Valdrakken and Ohn’ahran Plains and are visible on your map.The journey is long, so be sure your drake is well rested. Zaralek Cavern Meet New AlliesAs the heroes of Azeroth venture into the underground expanse of the Zaralek Cavern, they will be aided by and build Renown with the local inhabitants found within. Drogbar The familiar faces of the drogbar can be found in Glimmerogg.
They now have their own culture and embrace some unique interests—lifting heavy things and snail racing. Players can participate in their own race by nudging along a crystal-shelled gastropod named Brulee to gain the Zoom! Achievement and get their own snail pet. Watch out for the slime trail.
Niffen These busy molefolk might not see much with their inferior eyesight, but with their distinct nose, their sense of smell is mighty. The entrepreneurial and friendly niffen make their home in Loamm and they’re always willing to barter and trade with outsiders who pay them a visit. Players can unlock their Renown tracks for rewards once they complete the first chapter of the Embers of Neltharion campaign.
Read more on wowhead.com