Zone Omicron "Grave of Cuture" is the Stage 5E of G-Darius, It is the abandoned Darius city sets during a thunderstorm, the first half of this stage's background is unique for being completely dark, with only lightning strikes making anything visible to the player. Each flash of lightning reveals the ruins of a horribly destroyed city. Later on, for a very short time, the player can also see that the Sperm Whale boss has been watching them. This zone splits in Area U' and Area V' but it's the underwater version of Zone Lambda.
Area U': same as Area U of Zone Lambda
Area V': same as Area V of Zone Lambda
The Silver Hawks escape from G.T.'s explosive death, as both ships arrive to planet Darius, the destroyed remains of G.T. are drifting in space. Suddenly a mysterious ship retrieves G.T.'s carcass and heads to an unknown destination.
Darius Odyssey Explanation
Although G.T. was destroyed, Sameluck and Lutia are unable to return to Amnelia since their Silver Hawks are unable to travel back. Instead, they land on the closest planet they've found: Darius.
At the same time, a spaceship from Belsar's fleet picks G.T.'s carcass and leaves. This ending is called "The Creation of the Belsar Army".