- Secret HAL room in Revenge Of The King
In Stage 2, go to the area with the stone switch. Hit the switch to break the blocks. Go to the left, and press Up to find a door. Go through it, and defeat the mini-Boss. Continue to the right, and you will eventually reach a room with blocks spelling 'HAL' and an Invincible Candy.

- Bonus mini-games
Successfully complete the indicated task to unlock the corresponding mini-game:

The Great Cave Offensive	Successfully complete Spring Breeze.
Milky Way Wishes	Successfully complete Spring Breeze, Dyna Blade, The Great Cave Offensive, Gourmet Race, and Revenge Of MetaKnight.
Samurai Kirby	Successfully complete Meta-Knightmare Ultra.
Revenge of The King	Successfully complete Milky Way Wishes.
Meta Knightmare Ultra	Successfully complete Revenge Of The King.
Helper to a Hero	Successfully complete The Arena.
Revenge of MetaKnight	Successfully complete Spring Breeze, Dyna Blade, The Great Cave Offensive, and Gourmet Race.
The Arena	Successfully complete Milky Way Wishes.
Gourmet Race	Successfully complete Spring Breeze.
Dyna Blade	Successfully complete Spring Breeze.
Sound Test	Successfully complete the first six games.
Megaton Punch	Successfully complete The Arena.
The True Arena	Successfully complete The Arena, Helper To Hero, Revenge Of The King, and Meta Knightmare Ultra.

- Gold corkboard frame
Get a 100% game completion on your saved game file.

- Bonus movies
Successfully complete the indicated task to unlock the corresponding movie at the 'Theater' menu:

Movie 34	Successfully complete The True Arena.
Great Escape-Hero Up High	Successfully complete the Great Cave Offensive
Spring Breeze	Successfully complete Spring Breeze.
Milky Way Wishes	Successfully complete Milky Way Wishes.
Tomorrow's Be victorious ind	Overcome DeDeDe in Spring Breeze.
To The Battlefield	Successfully complete Milky Way Wishes.
Revenge of the King	Successfully complete Revenge Of The King.
Dyna Blade	Successfully complete Dyna Blade.
Halberd Scenes 4-6	Successfully complete Revenge Of Meta Knight.
Marx's Mad Plan	Successfully complete Milky Way Wishes.
Halberd Scenes 1-3	Successfully complete Revenge Of Meta Knight.
Flying Fortress Kabula	Successfully complete Revenge Of The King.
Great Cave Offensive	Successfully complete the Great Cave Offensive
Staff Credits	Successfully complete Milky Way Wishes.
Friends and Sun	Successfully complete Revenge Of Meta Knight.
Movie 31	Successfully complete Meta Knightmare Ultra.
Kirby's Triumphant Return	Successfully complete Milky Way Wishes.
Live Healthy	Successfully complete Dyna Blade.
Grand Opening	Watch the introduction sequence.
Halberd Scenes 7-9	Successfully complete Revenge Of Meta Knight.
Movie 00 (Original Kirby Movies)	Successfully complete Helper To Hero with all characters.
Gourmet Race	Successfully complete Gourmet Race.
Revenge of Meta Knight	Successfully complete Revenge Of Meta Knight.
Movie 35	Get a 100% game completion.

- Mario series reference in Spring Breeze
During the battle against King Dedede, go to the far left or right of the arena to see various characters from the Mario series.

- Alternate game selection menu music
Successfully complete The Arena to change the game selection menu music.

- Sound test
Successfully complete six mini-games to unlock the 'Sound Test' option. Alternately, successfully complete Milky Way Wishes.