While running AC on explorable mode, during the event where the burrows spawn on the first story path, we encountered burrows that were unable to be hit. 3/5 members of our party kept getting “obstructed” or “miss” constantly.
We tried moving around into different positions but it didn’t seem to effect it at all. Attacks that rained down from the top however seemed to damage them. We had to stop at that point in the run because it harbored our progression. Also I’ve seen this same kind of bug happen in DEs where attack-able thing spawn up from under the ground.