Gooigi

"Allow me to introduce this green doppelgänger. I call him Gooigi!"

- Professor E. Gadd

Gooigi is a clone of Luigi featured in the Nintendo 3DS remake of Luigi's Mansion. He appears in Luigi's image, but is entirely composed of green goo, hence his name, and wields a gooey version of the Poltergust 3000. He was created by a future Professor E. Gadd.

While Luigi was exploring the Old Clockworks during Luigi's Mansion: Dark Moon, Professor E. Gadd sent Gooigi back in time to the events of the original Luigi's Mansion, outsourcing his testing to his and Luigi's past selves.

In the game, Gooigi serves as the second player in the game's new multiplayer mode. He begins with only 50 HP and is vulnerable to fire, burning and melting very easily, but can revive indefinitely if his health reaches zero. When Gooigi is not being played by a second player, he is seen in the background of The Lab staring at some test tubes.