Get the key!
Get the key! is a minigame found in Mario & Sonic at the Olympic Winter Games. To gain access to it, the player has to get Luigi to join their team. In Sparkleton, Mario and company will find a door with a keyhole. If Luigi is in the team, he tells the party that he'll go look for it. However, a Boo appears and scares Luigi, who bumps into a tree and makes the key fall. The Boo then takes the key and challenges Luigi to take it from him in the minigame.
The minigame starts with five boos. Luigi has to find out which one of them holds the key. In order to do so, he has to collect all of the four green batteries without touching a single Boo (or else he'll scatter the batteries), and turn on the lights. When done so, the Boos will turn invisible and the player can see the key floating. Luigi has to pick it up before the lights go out again.
Avoid Boo and get batteries to turn on the light. Use the light to find the key!