Gooey is a friendly blob of Dark Matter. He first appears in Kirby's Dream Land 2, where he is found in bags after defeating certain mid-bosses. He only appears when the animal friend that's found in the bag is already paired with Kirby when the bag is opened, and he replenishes Kirby's health. Gooey returns in Kirby's Dream Land 3, where he can be controlled by the CPU or by the second player. Gooey has similar powers to Kirby, except that he licks up enemies, instead of inhaling them. He can lick up stars, and can devour enemies underwater, while Kirby inhales stars, and often cannot eat underwater. However, unlike Kirby, Gooey can't eat two enemies at the same time. During the game's final battle in space, Gooey's flying form is similar to Dark Matter's appearance, but with a different color scheme and facial features. It costs Kirby one square (2 HP) out of five to summon Gooey.
Gooey's use of his tongue to ingest enemies is similar to the abilities of Yoshi from the Mario series.
The fact that Gooey is a friend of Kirby's, proves that a being made of Dark Matter has its own free will, yet most will choose to follow their leader, Zero.
Gooey is one of the few beings who uses his tongue as a method of attack. The others are Chameleo Arm, Peloo, Slobba, and Fangora.
When swallowed, Gooey will give Kirby 2 HP in Kirby's Dream Land 3.