Troll-Skullz is a Rogue army faction introduced in Total War: Warhammer II. It is led by Wharg and can be found roaming in (???).
Their army is composed of monsters.
Possible Spawn Points
Eye of the Vortex
Bring anti-large units otherwise this faction will literally "troll" you.
As a Dawi this is a Slayer and Giant Slayers dream scenario (as well as your Thunderers and Cannons, maybe even go wild and get a Flame cannon to mitigate the Trolls' regeneration and punish their fire weakness).