Dark Matter, along with Nightmare is one of the main antagonists within the Kirby series. It's a bit more confusing though. Dark Matter can take on many shapes and forms, and also has the power to possess others and make them do what it would like. Often it is King Dedede that falls under Dark Matter's spell. It's unknown where Dark Matter came from, or why it seems so fixed on taking over everything it can with its terrifying darkness. But whatever the reason is, Dark Matter is very evil, very mysterious, and very dangerous. It's also unclear if the many different forms of Dark Matter are each separate, or all some form of the main Dark Matter. One common trait that it seems to always have is one large eye, often bright (blood) red.
In this game, Dark Matter has possessed King Dedede and taken over the Rainbow Islands. Kirby must gather all of the sacred rainbow drops which will come together and create a powerful Rainbow Sword which has the power to defeat Dark Matter. In this game it has two forms, the second one guessed to be his "true form".
Dark Matter once again possesses King Dedede and proceeds in spreading a giant cloud of darkness over Dream Land, taking over the minds of several inhabitants on the way. Kirby must gain the Love-Love Stick (Heart Rod) to defeat Dark Matter once again.
This time Dark Matter takes over the small planet of fairies, Ripple Star. Ribbon escapes with the planets relic, the crystal, and three smaller forms of Dark Matter chase after her and take over Kirby's friends: Waddle Dee, Adeleine, and King Dedede. When Kirby defeats those and finally makes it back to Ripple star he meets another form of Dark Matter, Miracle Matter. Even though it appears so, Miracle Matter is not the final boss. Kirby still must go on to fight the real final boss, 0².
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