King Boo kidnapped Daisy, Luigi is just about to save her when a Crazed Shy Guy comes and blows up King Boo's Mansion!! Luigi, Daisy and King Boo escape, and agree to work together, then they head off to defeat the Shy Guy!
- Luigi - The Most Average Character, Has good Jumping, Speed and Strength
- Daisy - Fast and Good Jumping, but bad power
- King Boo - Strong and Good Jumping, But slow
W1 - Sarassaland - Boss: Magic Guy
W2 - Ocean City - Boss: Mermaid Guy
W3 - Frozen Peaks - Boss: Freezie Guy
W4 - Deep Forest - Boss: Hermit Guy
W5 - Mystery Plains - Boss: Beezo
W6 - Fly High Sky - Boss: Fly Guy
W7 - Spiked Mountain - Boss: Adventure Guy
W8 - Lavcano Vol - Boss: Dry Guy (not user, undead shy guy)
W9 - King Boo's Mansion - Sergant Guy (final boss)
- Snifits (manage Item, and 1-up houses)
- Mario (Luigi's Helper)
- Peach (Daisy's Helper)
- Petey Piranha (King Boo's Helper)
- Boo (Appear as King Boo's Followers)
- Toads (Luigi's Followers)
- Piantas (Daisy's Followers)
- Shy Guys
- Koopa Troopas
- Buzzy Beetles
- Hammer Bros.
- Mecha Guy
- Bullet Bills
- Fire Bros.
- Boomerang Bros.
- Ice Bros.
- Koopa Kids
* Waluigi, Diddy Kong and Birdo were going to have a role, but were scrapped. They're thought helpers were Wario, DK and Yoshi, respectivly.
- King Boo actually speaks real words for the first time.
- Meta Knight makes a cameo in world 1, chasing after King Dedede, who has kidnapped Kirby,which is a reference to Meta Knight: Hero of Dreamland.
Charles Marinet as Luigi, Mario
Deanna Mustard as Daisy
Samantha Kelly as Peach, Toad
Mike Vaughn as King Boo, Boos
Lani Minnella as Petey, Piantas