Likely the first dungeon you'll head into. Available immediately at level 20.
While in game, Press Start> Go to Quick Matching> Go to Instance Matching and press
on Bastion of Lok then
The bosses (or BAMs the game refers them as) are:
Everything is sorta tank and spank. Dont stand in red circles. Its not a mechanics heavy dungeon. Achievement pops right as you kill Murdranak
NOTE: There is a cut off to this dungeon popping up on the queue list. At 27 you'll see the manor instead. If you miss it early, you can just go back at a high level and solo it or find a random group happy to take a high level through (spam chat option)
There is a known issue where completion might not always award an achievement. If you've unlocked the corresponding achievement in game but not on Xbox, you'll have to wait for a fix from En Masse.
Should be fixed now but keep an eye out.