Blocks fall in pairs from the top of the play area. The way these two block sections appear and fall is very similar to the pills in Dr. Mario. However the overall gameplay and objective is different.
When you line up two animal blocks in a row horizontally or vertically, the matched pair and everything in-between will disappear. If a different animal is in the way, it will not work. If there are more than two of the same friend in a row, then all that qualify will disappear. Any stars or obstacles in the middle of two lined up matching animals will also disappear.
The objective of the game is to score stars by placing one or more stars between two matching friends, which causes the friends and the stars to disappear, adding to the score total.
In Round Clear mode, once you have won the specific number of stars required for that stage the stage will end. Challenge and Time Attack work differently, since they are based on time. After a specific amount of time passes, you will be judged based on how many stars were gathered within the time given.
There are 3 major block types: Kirby's friends, stars, and obstacles. Here is how each work: