Before Luigi starts this mission, Professor E. Gadd warns him that several things in the mine, especially the crystals, have unusual properties, and that the Dark Moon piece is somewhere in there. He also says he has a Toad assistant doing research, but is not responding to his calls, and assumes he fell asleep in the Chalet.
After Luigi gets pixelated to the mine, he encounters several Hiders and a Sneaker, but there is no sign of the Toad. E. Gadd then tells Luigi to look in the Fishing Hut for it, and he does, but the Toad is so elated that he jumps with joy, cracking the ice in the hut, and sending both himself and Luigi plummeting.
After Luigi and the Toad are sent underground, E. Gadd tells Luigi to look for the elevator in the Airway to come back up to the Chalet, but once Luigi arrives, the Toad realizes that the zip line that leads to the elevator cannot be activated. Luigi and the Toad search for an alternate route. They do, but once they are about to enter the Airway, they are ambushed by a large group of Sneakers. After Luigi defeats them, they discover a bridge leading directly to the elevator, but it is precariously uneven. Luigi fixes it up, leads the Toad back to the Chalet, and the mission ends.
Find the elevator to the Chalet, and use the Pixelator Screen there to send the Toad back to the Bunker.
The Boo of this mission is hidden inside the Terminal. After Luigi gets both of the keys from here, if he comes back, he will discover a barrel to the right of the door is missing. If Luigi shines his Dark-Light Device on it and sucks up all of the Spirit Balls that come out, the Boo, named Boofoon, reveals itself.
I can't seem to get a hold of my Toad assistant at the Chalet. He's probably napping in front of the fireplace again. It's so hard to find good help these days!
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