The Lair is located in the small cove at the northern-most tip of the subzone Da Big Sand, to the northwest of the Greenskin Chapter 5 "Nogaz's Boyz".
The entrance is a partially submerged cave behind some logs and rocks.
Approaching the lair will trigger an Achievements unlock. (Not implemented yet)
Killing Karerg drops level 36 blue gloves:
|Warrior Priest||Bright Wizard||Knight of the Blazing Sun||Witch Hunter|
|Archmage||Shadow Warrior||Swordmaster||White Lion|
|Shaman||Squig Herder||Black Orc||Choppa|
|Disciple of Khaine||Sorcerer||Blackguard||Witch Elf|