In Sonic Chronicles: The Dark Brotherhood, finding and accessing Angel Island is the driving motivation for Sonic and team during Chapters 3 through 5. Exploiting the connection between the Chaos Emeralds (which they have) and the Master Emerald (which they want), the Nocturnus are able to draw Angel Island away from the G.U.N. fortifications in Mystic Ruins, and position Knuckles' home over their own territory in Dr. Eggman's former stronghold, Metropolis.
With Eggman's help, the party are able to access the ruins of Metropolis and ascend to Angel Island by hijacking a Nocturnus sky skiff. Although the transport gets shot down, Sonic and Knuckles make it to the Island, and fight their way towards the ancient temple where Imperator Ix is attempting to access the Master Emerald chamber.
The fight against Shade and Ix on the steps of the giant pyramid is one of the most difficult in the game. After almost being overwhelmed by several waves of Nocturnus troops, Sonic's group is saved when Eggman and Tails teleport up to the island and banish the bulk of the enemy forces back to the Twilight Cage. However, they aren't in time to stop the Imperator, who (after trying to kill Shade for insubordination) breaches the Emerald Shrine and escapes with the Master Emerald. Cue Angel Island falling out of the sky.
The music used here is a remix of Collision Chaos (Bad Future) from the Japanese version of Sonic CD.