I eliminated an AI and some of their units turned white in a neighboring AI’s town.
Two units were idling between an ovoo and a house. They were blocking my rams from pathing through. I selected my army to kill them but they were not able to be targeted. Cursor kept highlighting the Ovoo. Since neutral units also can’t be targeted by attack-move commands, those two archers were essentially an immune wall.
Thank you for the report @Heftydogg! This is something we are looking into.