Dark Matter (referred to as !? in Kirby's Dream Land 2's bad ending) and related characters are major villains in Kirby's Dream Land 2, Kirby's Dream Land 3 and Kirby 64: The Crystal Shards.
Dark Matter is often depicted as a single entity, but has later shown to have the capability of splitting into smaller, seemingly sentient black orbs; thus, the term "Dark Matter" may not necessarily refer to an individual, but rather any number of alike shadowy cloud figures.
Dark Matter typically takes the form of a shadowy sphere with a single eye in the middle, and is usually shown to have a ring of smaller orange (originally purple) spheres.
- The Japanese Hoshi no Kābī Tsū player's guide 「最新星のカービィ大百科」 states that Dark Matter targeted Planet Popstar because it grew jealous of Dream Land's lifestyle and suffered from loneliness due to the fact no one wanted to be its friend.
- In addition, it refers to the second form in Kirby's Dream Land 2 as Real Dark Matter (リアルダークマター).
- The swordsman form of Dark Matter has a laser attack with the same sound as Laser Ball from Kirby's Adventure.
- Dark Matter appears capable of altering its form so it is suited to whatever task it must carry out. This is first seen when Kirby first confronts Dark Matter in Kirby's Dream Land 2, where it assumed the form of a masked swordsman, presumably to combat against the overwhelming strength of the Rainbow Sword. In subsequent appearances except Kirby Mass Attack and cameos of the swordsman form, it would only possess others to combat Kirby or fight in its natural state.
- In Kirby's Dream Land 3, Dark Matter was a simple circle with a white eye with a red iris and pupil, and ora