To unlock an extra fifth character, insert the GBA game Kirby and the Amazing Mirror (it doesnt seem to matter what region) into the DS and load up your save file on Kirby DS. A message will pop up and now the extra character will be available
To unlock the first new character, Waddle Dee, beat the game once. He is exactly the same as Kirby except for the fact that he has four life and cannot obtain powers. The second new character, King Dee Dee Dee, is purchasable for 20 medals once you get Waddle Dee. He is large, has 7 life, and swings his hammer when you touch him. He cannot get powers either. The third new character is Metaknight. He is purchasable for 25 medals once you get King Dee Dee. He is almost twice as fast as Kirby and cannot get powers, but he only has 3 life. The game will keep track of what stages you beat with each character.
An alternative way to unlock the 5th secret character is to complete the final level (Drawcia's Castle) while having the game "Kirby's Nightmare In Dream Land" (Region does not matter) inserted in the GBA slot in the Nintendo DS.
You need to get the appropriate amount of medals before you can unlock these in medal swap. Some of these cannot be unlocked until you meet certain requirements:
Normally, you would have to unlock Waddle Doo by beating the game with the other four balls. However, if you own a copy of Kirby: Nightmare in Dreamland or Kirby and the Amazing Mirror, place it in the GBA slot of your DS when you beat the game. The next file you load will have Waddle Doo unlocked.
When you beat the game 100%, when you load up the title screen it will be blue instead of the normal white.
To unlock these six tracks of the end music, you have to beat the level World of Drawcia for the first time with Kirby. When you start up your file again, the new tracks are already added to the sound test. They are:
24 - The World of Drawcia
40 - Drawcia Demo
41 - Dracia Sorceress
42 - Drawcia Soul
43 - Ending Cinema
44 - Credits
When you pick up a powerup that lets Kirby hover, such as Beam or Spark, hold Kirby in midair by pressing him with the stylus. He will hover until the stylus is removed, and the paint supply recharges while he hovers. This is useful for when Kirby is too high in the air to recharge normally.
