Kirby's Star Stacker is a puzzle game originally released for the Game Boy console in 1997 and later re-released on other platforms. The game takes place on the planet Popstar, where Kirby must stack same-colored stars to make them disappear and earn points.

The goal of the game is to stack three or more stars of the same color vertically or horizontally. Stars fall from the top of the screen, and the player must rotate and move them to fit into the existing stack. If the stars pile up too much and reach the top of the screen, the game ends.

There are several game modes in Kirby's Star Stacker, including the single-player mode where Kirby must complete a series of increasingly difficult levels, and the two-player mode where two players compete to see who can stack the stars faster.

As the player progresses in the game, they encounter enemies and bosses that try to make the task of stacking stars more challenging. Kirby can use his special abilities to get rid of the enemies and gain an advantage over his opponents.

Overall, Kirby's Star Stacker is a fun and challenging game that requires skill and strategy to complete successfully. With its addictive puzzle mechanics and colorful and fun gameplay style, it's a classic Game Boy game that remains popular to this day.