Final Chase' is the fourteenth stage in the Dark storyline of Sonic Adventure 2 and the fourth and last stage playable with Shadow. It represents Shadow's run through the ARK's underside to intercept Sonic after finding out he's alive and heading towards the Eclipse Cannon. It is the equivalent to Sonic's final stage, Final Rush.
After finding out that he may not be the real Shadow and that Rouge is a government agent, Eggman informs him that someone is headed for the Eclipse Cannon. Shadow immediately heads out to destroy the intruder. He then finds Sonic and defeats him while Eggman places the final Chaos Emerald into the Eclipse Cannon.
This stage consists of numerous rails but the main gimmick of this stage are "gravity cylinders." These cylinders have a magnetic pull that drawls Shadow to them. They only allow one direction when running on them: up or down. Some parts of the stage completely consist of these gravity cylinders.
Shadow's Mystic Melody upgrade is found here.