Super Mario Sunshine
"Luigi's Mansion" introduces two characters, Professor Elvin Gadd, or E. Gadd for short, and King Boo. E. Gadd has reappeared in other Mario games, such as "Mario Party 6" and '. E. Gadd is referenced in "Super Mario Sunshine" as the creator of Mario's F.L.U.D.D. device and Bowser Jr.'s paintbrush. He also appears as a playable character skin in "Super Mario Maker". King Boo has also reappeared in other games, either as a boss (including "Super Mario 64 DS" and "Super Princess Peach") or a playable character (including ' and "Mario Super Sluggers").