Kirby discovers the ancient Dimension Gate, a link between dimensions. He does not enter because he doesn't know what is on the other side, but the next morning, the citizens say that King Dedede had entered the gate! Meta Knight and Kirby organize a meeting, and all of the heroes in Dreamland agree to enter to find the king. They all head in, but it closes behind them and leaves them trapped in a dark void. They must rescue King Dedede and find a way out, while along the way teaming up with various others from different dimensions.
Kirby Dimension Gate uses a modified version of the Kirby Super Star Ultra engine. A unique feature is that each character is capable of levelling up to learn new moves. Kirby and Keeby, who absorb enemies powers, can level up each power individually. You can have two helpers with you at a time; helpers do not level up, and any enemies they defeat give the current character you are playing as experience.
- Kirby is capable of speaking in this game; however, he has a childish voice and often pronounces certain words wrong after which Meta Knight or another character corrects him.