Kirby's Dream Land 2 is the first in a sub-series of Kirby games with a darker tone, and requiring the collection of extra items to fight the true final boss.
A blobby new villain, Dark Matter, destroys the seven Rainbow Bridges that connect the Rainbow Islands. Kirby joins with three new Animal Friends: Rick the hamster, Coo the owl, and Kine the ocean sunfish, to save the islands and defeat Dark Matter, who has possessed King Dedede.
Copy Abilities return from Kirby's Adventure, with new transformations when Kirby is riding an Animal Friend. These altered abilities are required to reach the seven Rainbow Drops and truly defeat Dark Matter.
But who sent Dark Matter to do his evil bidding? This question is answered in Kirby's Dream Land 3...