Posts from Patch 1.6
As for 4-3, it seems to refer to the red Inferno creature that respawns at the edge of the map. This is a known bug where it doesn't move. It occurs if it was Monster Week, and one of the units respawned on the road leading to the Dungeon or on the first tile near the entrance to the Dungeon. Then, the script doesn't trigger, and the demon remains stationary. Therefore, it's recommended to replay all Monster Week scenarios in this mission.