Boo, is an icon to the Super Mario series as much as any of the other side characters that are highly recognizable, like Toad or Yoshi. Boo serves as the primary ghost enemy of the Super Mario series and is a playable character in a lot of the other Mario games. He has been portrayed very differently in each game that he has appeared in.

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The levels that will be presented are some that are the most enjoyable to play through where the lovable ghosts or King Boo were present. These levels are not only some of the most entertaining Boo levels but also some of the best in the Super Mario series.

10 King Boo Down Below - Super Mario Sunshine

King Boo In Super Mario Sunshine

King Boo Down Below is the fifth level in the Serena Beach area of Super Mario Sunshine. It is a level that is extremely hated by the Super Mario Sunshine speed-running community as the level is a boss fight that revolves heavily around a random number generator. What that means is that in order to defeat the boss players must get lucky with the red pepper spawns.

For the majority of players that don't speed run, the boss is a lot of fun and this is one of the cutest renditions of King Boo as he looks happy and hungry through the entirety of the fight.

9 Go On A Ghost Hunt - Super Mario 64

Super Mario 64 Boo

Go On A Ghost Hunt is the first level in Super Mario 64 where players get to go into Big Boo's Manor. Big Boo's Manor is a haunted house-themed area where players have to do different missions that involve encountering Boo enemies. The first level is one of the best as it feels like a true ghost hunt.

Players will need to search around the map and try to kill all the Boos in order to unlock the area's star. It's a great way to introduce the area and pushes players to explore different rooms.

8 Luigi And The Haunted Mansion - Super Mario Galaxy

Luigi And The Haunted Mansion Super Mario Galaxy

Luigi's and the Haunted Mansion in Super Mario Galaxy introduces a lot of really neat game mechanics and some different ways of interacting with Boos. The Boos in this map will die if they are hit by light, so they will act as obstacles but can be dealt with in a puzzle-like structure if players figure out how to get the Boos to the light.

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Mario also gains a Boo transformation which looks like a Boo with a giant Mario face. It's one of the silliest-looking transformations but lets Mario access areas with bars that he wouldn't be able to access without it.

7 Soda Jungle Which-Way Labyrinth - New Super Mario Bros. U

Soda Jungle Which-Way Labyrinth New Super Mario Bros

New Super Mario Bros. U made a maze-like structure in the way that it presented its ghost house level in the Soda Jungle Which-Way Labyrinth. The player starts off in an area with 5 different doors, and they must be able to navigate through the house that's filled with different types of Boo enemies as well as different traps.

The boos in the level work similarly to those in previous games but Mario has a golden lamp Yoshi that can eat any of the Boos that get too close if Mario is looking at them.

6 World 2: Castle - Super Mario Bros. 3

Super Mario Bros 3 World 2 Castle

Super Mario Bros. 3 is iconic to Boo as this was the first game that the Boo enemies made their appearance. The design in this game is actually one of the most threatening designs than those that were in some of the future games. Well, when they are chasing players. While chasing, they will show their sharp teeth and rush hurriedly toward Mario.

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If Mario makes direct contact with the Boos by looking at them then they'll put on an adorable scowl that makes the player feel kind of bad for the little murderous ghosts.

5 Pumpkin Zone: Level 2 - Super Mario Land 2: 6 Golden Coins

Pumpkin Zone In Super Mario Land 2

Super Mario Land 2: 6 Golden Coins had an entire zone inside a pumpkin that looked like a pumpkin when the player entered it on the Island. The second level is where things get fascinating as it will have the player traveling through a graveyard-like area and when the player goes underground they will start to encounter Boos.

It's a well-designed level that gives the player a feeling of exploring crypts in the Mario world. The Boos in this map feel like less of a threat, but they are a nice addition to the way in which they decided to make the level.

4 A Beam In The Dark - Super Mario 3D World

A Beam In The Dark Super Mario 3D World

If anyone's ever dreamed of becoming a light that could murder ghosts then this level is for them. This level's actually for everyone but turning the player into a light component is so out there that it's laughable yet such a fun experience. A Beam in the Dark in Super Mario 3D World will have the player trying to target different ghosts with light while initially on a moving platform.

The level then adds some labyrinthian areas and increases the difficulty of the moving platform segments to come. It'll have the players quickly flicking back and forth trying not to fall off the platform and kill enough ghosts to stay alive.

3 Donut Ghost House - Super Mario World

Donut Ghost House Super Mario World

The way that the game introduces the player to Donut Ghost Hole in Super Mario World is enough to induce slight chills into the player. The player is dropped off by Yoshi in front of a creepy house that says, "Ghost House," on a sign on the top of a door that bursts open by itself.

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There are areas that the house presents that will try to overwhelm Mario with the number of Boos that appear on the screen and try and go after Mario. The player will need to manage all the different ghosts and puzzles while also trying to figure out what the best possible direction to go can be.

2 Kero Sewers - Super Mario RPG: Legend Of The Seven Stars

Super Mario RPG Cover

Super Mario RPG: Legend of the Seven Stars is not like any of the other Super Mario games on this list as this game plays more like an RPG than like a platformer. Much like some other Boo levels, Kero Sewers presents a labyrinth structure in the way in which it must be completed. There are a lot of different ways players can get lost.

The level also presents Boos in a sewer instead of the Haunted House location where he mainly tends to be. The design is also really neat as the Boo will have its regular Boo face and then distort it to make a scary Boo face.

1 World 2: Haunted House - New Super Mario Bros. 2

World 2 Haunted House New Super Mario Bros. 2

The giant Boo that appears in the Haunted House in World 2 of New Super Mario Bros. 2 is much creepier than any of the other Boo iterations. It legitimately looks like something that would pop up in a Horror movie, but, instead, it's in a Super Mario game where it slowly approaches Mario with its sunken-eyed stare.

It is not one of the hardest levels in the game but the slow chase and the level constantly introducing other Boos that the player must avoid makes it so that player is constantly on their toes trying to make sure they don't get killed by one of the enemies.

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