Shadow the Hedgehog: Story Cycle 4: Part 8: Vs. Sonic & Diablon (Slightly Dark - Dark Ending)
Here's the result of you completing the Dark Mission of Black Comet.
Shadow, upon take out numerous GUN forces throughout the Black Comet, is confronted not only by their Commander using Diablon but also Sonic, himself.
The GUN Commander reminded Shadow that he was responsible for getting everyone in Space Colony ARK killed. Shadow thought that he was made to bring order to humans, and that involved eliminating them as a punishment for their own sins.
He plans to defeat Diablon, and also Sonic, too!
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This version of this boss is almost virtually exactly the same as fighting the Final Haunt version of them. Just do what you may have done before with using Sonic to reach Diablon's head, forcing him to the ground, and going all out on his head with a weapon if you're able to unleash Dark Shadow.
Finish this dual boss, and then get 7th and final Chaos Emerald!
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As Shadow gathered together all 7 Chaos Emeralds, Sonic, with what little strength he had left, begged for Shadow to tell him why he's siding with the Black Arms...
This is Shadow's Slightly Dark - Dark resolve of who he is:
"I'm Shadow the Hedgehog. The ultimate life form born to protect and serve the dark lord, Black Doom. With the power of these Chaos Emeralds, this world will become the dark empire.
This is *WHO I AM.*"
He then performed his evil laugh. The world was truly doomed. Black Doomed, per se...
The Slightly Dark ending theme is "Almost Dead" from Powerman 5000. A hardcore theme about giving a middle finger to life and death, Heaven and Hell. Throwing it all away as a being who believed that everyone was ready to die into nothingness.
If you're gonna play for all 10 endings, you're gonna be hearing this theme the most, as it plays for both Slightly Dark AND both Pure Dark endings. No other ending theme gets this much.
So stay tuned for whatever path I bring Shadow through for Story Cycle 5!