The ARK (Shadow the Hedgehog)
From Sonic Retro
The ARK is a stage in Shadow the Hedgehog that takes place along the same route as Final Chase.
Purpose
After either taking out G.U.N. in The Doom or setting off the Giant Bombs in Central City, Black Doom transports Shadow to the outside the Space Colony ARK. After an explanation of the Colony's importance to their plans, Black Doom sends Shadow inside the Colony to destroy the defense systems.