I had problems with the drones when I tried to summarize a game started in version 9.0 in version 9.1. They were two problems: one is the one that describes, the drones only appeared when I approached a lot of them, after they appeared, they worked normally. But it happened a few times. The second, which occurred frequently, was that they did not move and did not explode after the hit points were over, "they were dead in the sky." When I attacked the Drone Base, in which several drones are launched, the game crashed and fell to the desktop. After that I could not even carry it anymore, always drop to the desktop. I did not have time to start a new game after this , so I do not know the current status of the drones.