Have Axl and anyone else and Layer as navigator. Get to the area where you see a flying guard. Layer will say that he is copyable. Get the Copy chip from him and go back to the place where the two bats were hanging. Activate the guards copy DNA. You will see a small hole in the area with spikes around it. Fly into the hole to get a Rare Metal. Additionally, have Zero and someone else with Palette as navigator. When you get the T breaker and the weapon from Gravity Antonion, return to this stage. Get to the part where Palette says you can break the floor in this area. Get out the T Breaker and use Gravity Antonion's move on the floor. It will break, and you will fall down to the Rare Metal.