Luigi's Mansion 3 is set in a massive hotel that is more akin to a skyscraper than a mansion, with themed-floors that contain gyms, swimming pools, and even a castle. The expanded setting of the game means that many fans are asking how long Luigi's Mansion 3 will take to complete.
According to HowLongToBeat, the original Luigi's Mansion could be finished in around six hours, while Luigi's Mansion: Dark Moon took around fourteen hours to beat. Luigi's Mansion 3 can take longer to finish, depending on how far the player wants to go with the game.
The amount of time that Luigi's Mansion 3 takes to complete depends on several factors. There are collectibles strewn throughout each floor and it's possible to buy items from Professor E. Gadd that give a general idea of their location. The two collectibles are the Gems that are hidden behind puzzles, or the Boos from the Super Mario Bros. series that need to be hunted down.
If the player doesn't care about going after these collectibles, then the story of Luigi's Mansion 3 will take between 15 and 20 hours to complete, depending on their skill. Luigi's Mansion 3 isn't a difficult game, and the addition of Polterpup's Golden Bones makes it all the easier. The Golden Bones are essentially extra lives that can be purchased from Professor E. Gadd's shop and they can help Luigi brute force his way through the boss battles and some of the deadlier puzzles in the game.
The players who want to find the Boos will add a few extra hours to the game, It's possible to discover the general location of the Boos by purchasing items from Professor E. Gadd, but the player still needs to follow the HD Rumble in order to find their hiding spot. If the player screws up, then the Boo will flee to a new position. The Boo hunt will also be a lot harder for people playing on a Nintendo Switch Lite, as there doesn't seem to be an alternative mechanic for people using controllers without HD Rumble, so finding the Boo could come down to chance.
The gems are significantly more challenging to find, as there are 102 of them and almost every one is hidden behind a puzzle. Like the Boos, it's possible to buy items from Professor E. Gadd that show the rooms that the gems are in, but that only narrows down the location and not the method. Acquiring all of the gems is a tricky task that can easily add five to ten hours to the game.
In short, the really skilled players who race to the finish line could probably finish Luigi's Mansion 3 in under fifteen hours. A regular playthrough will take 15-20 hours, hunting the Boos will add roughly another 2-5 on top of that, and the gems can add another 5-10.
Luigi's Mansion 3 will be released for the Nintendo Switch on October 31, 2019.