Dark Nebula

Dark Nebula (Dark Zero in Japan) is the final boss of Kirby: Squeak Squad, and (according to Kirby's Dream Collection: Special Edition) is also the first known member of the Dark Matter species to appear since Kirby 64.

Biography
At some point prior to the events of Kirby: Squeak Squad, Dark Nebula was sealed in a chest due to his evil, and seemingly forgotten. Early in the game, however, Daroach somehow became aware of the chest's power and accosted it from King Dedede's castle, believing it to be the source of ultimate power. After being stolen by Meta Knight (seemingly the only person with any idea what was actually in the chest) and subsequently Kirby (who thought it contained his strawberry shortcake that had been stolen earlier), the chest was seized by Daroach, who promptly opened it; Daroach is quickly possessed by Dark Nebula and turned into Dark Daroach, and then flees with the Squeaks into the depths of Gamble Galaxy.

Kirby chased Dark Daroach and defeated him, expelling Dark Nebula in the form of a black star: Kirby, now toting the Triple Star that Daroach dropped, chases Dark Nebula still deeper into Gamble Galaxy until both arrive at a crystalline battlefield, where Dark Nebula is defeated.

Attacks
Dark Nebula's main form of attacking is launching stars at Kirby from an angle (usually the side of the arena). Dark Nebula also has three alternative forms. While changing forms, the screen will flash white. If Kirby bumps into Dark Nebula, he'll be damaged (burned, frozen or electrocuted depending on what form Dark Nebula has).

Fire
In his fire form, he can shoot stars that can burn Kirby. His strongest attack in this form is releasing a large fireball that slowly approaches the ground and explodes, thus creating a vertical fire-blast. The easiest way to dodge this is to float by the side of the screen. The fireball can be destroyed to cancel out the attack. On the sides of the blast are rows of lingering flames. Also in this form, he will move at great speeds in angles. This physical attack is hardest to dodge, but only when Kirby is floating in Dark Nebula's range.

Electric
In his electric form, he will shoot stars at Kirby that can shock him. His physical attack involves moving in a zigzag pattern. His strongest attack is releasing four electric streams diagonally in all directions, then discharging them to create an electric frame that covers all sides of the arena. This attack is the hardest to dodge. The best way to dodge this is to first stand on the middle of the battlefield, wait for Dark Nebula's diagonal electric shocks to disappear, then, at the right moment, jump before Kirby gets hit by the electrical frame. It is also possible to duck under this attack, due to Kirby's small size.

Ice
In his ice form, he shoots out stars that can freeze Kirby. His physical attack involves going around the arena in a circle. Occasionally while doing this, he will float back and forth across the stage in an arc. His special attack is firing an ice laser at the ground, thus freezing it. This hinders Kirby's traction so that Dark Nebula's attacks can't be dodged as easily.

Trivia

 * The symbol for the Triple Star shows three stars, one blue, one green, one red, and these are also the colors of Dark Nebula's forms. This shows that, like the Triple Star, he uses the power of the three elements – fire, ice, and electricity – which are emphasized more in this game than in any other.
 * Dark Nebula's behavior has a passing resemblance to that of Miracle Matter. Incidentally, Dark Nebula is actually a being of Dark Matter, which was confirmed in the Hoshi no Kirby 20th Anniversary Encyclopedia. This would explain the similar coloration of Dark Daroach and Dark Matter's first form. It is unknown what relation, if any, it has to Zero and 0² other than a similar name and certain attributes. It is also unknown how or why it got in King Dedede's possession (if he even knew what was inside his treasure chest).
 * It is not known what Dark Nebula had intended to do once he had possessed Daroach and the Squeaks. Although if one views the Stage Select screen of the Gamble Galaxy, they can see that the final battle between Kirby and Dark Nebula takes place deep within a black hole that has seemingly appeared from nowhere. Due to the close proximity of the giant gravity well and Pop Star, Dark Nebula may have been trying to destroy the planet.
 * Kirby can easily dodge Dark Nebula by floating directly at the top corners of the screen.