There is an easy way to fill up a crow. After the last trap is neutralizing (where he is glad), press the lever again to bring in the original state. Go to Crow. The main chip is that the passage to the trap is not closed, so it’s better not to say with a raven (still a stupid), and at the entrance to the last hall to shoot him so that he wanted you. We run to the trap, press the lever and Hitler Caput!