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The true antagonist and final boss of Kirby: Squeak Squad. Its existence remains completely unknown until the endgame, where it is revealed that Meta Knight has kept its prison (a treasure chest that was thought to contain Kirby's strawberry shortcake) in captivity.
When Daroach stole the chest upon Kirby defeating Meta Knight, Dark Nebula immediately possessed the Squeak Squad leader and proceeded to carry out its evil plans. As expected, Kirby corrected his childish mistake by promptly laying the smackdown on the dark lord and saving the day once more.
It is heavily implied that Dark Nebula and Dark Matter are one and the same, especially with flavor text provided by a Japan-exclusive handbook from Kirby's 20th anniversary. This would explain its possession of Daroach, its association with darkness, and it having one eye
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