I was playing through the (I believe) 2nd mission of the Duergar clear out quest - the one where you see Kessel get taken at the ending cut scene. I was playing on PC, with friends, as Wulfgar on day 2 after release. As I hit the duergar with shield with Wulfgar’s Spin Move, the Duergar was hit up next to a Bolder and clipped down through the floor. The duergar was still present in battle, couldn’t move, but I assume the hitbox also clipped through, because I could only hit him with downward slams. This kind of happened again later with the same set up against the frost punching duergar when Wulfgar does his “drag the hammer and hit them away” move (I’m so sorry I forget the name of the moves) - but this time it only clipped half way for like a second.