Luigi's Mansion 3, the latest in the Mario spin-off series by Next Level Games, is out now, giving players a chance to hunt ghosts through a haunted hotel. With his friends and brother trapped in paintings throughout the hotel, Luigi must rely on his trusty Poltergust G-00 ghost-sucking vacuum cleaner, as well as a couple of companions, to clear the place out floor by floor.

Unfortunately, just because a floor has been cleared in Luigi's Mansion 3, it doesn't mean it will stay that way. For players wanting to truly rid the hotel of its mischievous denizens, the only way to do so is to backtrack to previously cleared levels to find the Boo hidden on each one. Boos are a classic Mario-series foe, with their lolling tongues and mocking laughs, who are always ready to outwit the player whenever they can. Here's our guide on how to track them down.

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Boo Hunting

Luigi has gained a new companion to help him track down Boos in Luigi's Mansion 3, a copy of himself made of sentient Goo which can act independently and vibrates when Boos are near. Imaginatively named Gooigi, this luminous doppleganger can be played by another player in the game's cooperative campaign mode, or simply dispensed from Luigi's Poltergust when needed if playing single-player.

Boos can always be found in interact-able containers, opened with the X button,  and the closer Gooigi gets to one containing a Boo the stronger he vibrates (as well as the Joy-Con of the player controlling him). It's worth making doubly sure which container is producing the strongest vibrations however, as an incorrect guess will cause the Boo to relocate, forcing the player to track him down all over again. Fortunately for those having trouble finding a Boo, Professor E. Gadd sells Boo Finders at his laboratory which can make locating the pesky ghosts much easier.

3 Luigi’s Mansion

Boo Busting

Once a player has discovered a Boo it'll pop out from its hiding place, make a quick quip based on its unique name and then vanish, locking all the exits of their current room. Unlike most ghosts in the hotel, and in the Ghost Hunt multiplayer mini-game, Boos can't be caught with a flash of the Strobebulb. Instead, players must first find the Boo with their Dark-Light, bound to the X button, and stun it by keeping it in the light.

Once the Boo has fully materialized and been stunned, all players need to do is treat it like any other ghost (except for the adorable Polterpup of course) and suck it up with the Poltergust. Once the Boo has been sucked in enough for the A Button prompt to appear, players should press it as rapidly as possible to slam the Boo into the ground to deal damage. If they're fast enough, it should only take two repetitions of this process before the Boo is contained, and the level cleared.

Luigi's Mansion 3 is available now for the Nintendo Switch.

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