Kirby's Return to Dreamland Cheats - Wii
Arena Mode - Beat the game once.
Extra mode - Beat the game once.
Sound Test - Beat the game once.
True Arena - Beat Extra Mode.
Kirby Master video - Complete both arenas, and get %100 on Main and Extra game.
All Characters in Arena - Beat Arena once.
All Character in True Arena - Beat True Arena once.
Ninja Dojo Game - Collect 15 Energy Spheres.
Scope Shot Game - Collect 30 Energy Spheres.
Unlock Hard version of Stage 5-5
Once you enter stage 5-5, float above the doorway and you'll see what looks like a window with three bars on it. Press up to enter it as you would a normal doorway and you'll go through a much harder version of the stage. The four sections are 1) Water Galborus, 2) King Doo followed by Dubior, 3) Kibble Blade & Gigant Edge, 4) Bonkers & Moundo. In addition to being against harder enemies, the fights take place in smaller than normal areas. You can get the four Energy Spheres and the path is available on EX mode.
Gain 30 Lives in the Bonus Jump Game
If you land on the 7th, 6th, 5th, 4th, 3rd, 2nd and 1st floors in that order in the bonus jump game at the end of every level, the jump to the 1st floor at the end will reward you with 30 lives, instead of 30 Stars.