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I am not afraid of you, fool! I fear only that infernal Poltergust 3000 you carry on your back! Stupid machine! But I am a KING among Boos! I swear it... I shall fear no mere house-cleaning device!!!
„
~ King Boo prepares for the final fight in Luigi's Mansion.
“
Mwahahaha! Now what do we have here? Why, if it isn't my old pal Luigi! Or is it Baby Luigi? I can't tell the difference. Hey, remember that time you trapped me in a painting for all eternity? Good times. But guess what? I GOT OUT! And now I'm painting the town RED! Yes, it was I who broke the Dark Moon! This power-enhancing jeweled crown of mine made it easy. And now that all the ghosts of Evershade Valley are under my control, it's time to take my rightful place as supreme ruler of your world! You, that annoying scientist, and all your friends will look great hanging from the wall of my throne room!
„
~ King Boo confronting Luigi at the end of Luigi's Mansion: Dark Moon.
King Boo is a major antagonist in Nintendo's Super Mario franchise, most notably serving as the main antagonist of the spin-off series Luigi's Mansion.
As his name suggests, he is the king of the entire Boo race. Initially seeking revenge against both of the Mario Bros. for their past victories against his minions, King Boo is defeated by Luigi and trapped in a portrait for years. After breaking free, King Boo becomes increasingly obsessed with outsmarting Luigi and torturing him as payback, to the point of using his own Boos as expendable tools and willing to destroy the entire universe just to win. Over time, he has become Luigi's arch-nemesis akin to how Bowser is to Mario himself, and to how Madame Grape is to Princess Peach Toadstool.
He is voiced by Toru Asakawa, who also voiced Bleak.
In the Luigi's Mansion series, King Boo appears as a large Boo with magenta eyes, an indigo tongue, and gray body that is sometimes shrouded in shadows. He also wears a gold crown that has a large magenta jewel embedded on top of it. In the first Luigi's Mansion game, his eyes and crown jewel were originally red in color and his tongue was originally blue in color.
In various other Mario games, King Boo resembles other Boos, albeit larger and wears a smaller crown that has tiny red and blue jewels on the rim instead of a large one on the top. Besides possessing the abilities of other Boos, including the ability to teleport, King Boo has a number of other magical powers. Notably, it should be mentioned that King Boo's power increases when he is in the presence of other Boos. King Boo also has the incredible power to materialize things out of thin air. He has also shown the ability to create Boos, bubbles, and blue fire, which he spits out of his mouth.
Although King Boo is a lot larger than regular Boos, he is not the largest of the Boos. However, even gigantic Boos like Boolossus follow his leadership despite their superior size. This is likely because he is the most intelligent and the most powerful of the Boos. King Boo seems to have a passion for gambling, as the entrance to each wing in Luigi's Mansion was modeled after a playing card suit (spade, club, heart, and diamond), he is fought atop a slot machine in a casino in Super Mario Sunshine, and (though this is non-canon), his Rival match in Mario & Sonic at the London 2012 Olympics Games is at Bingo Highway, a casino-themed stage from Sonic Heroes.
King Boo also has an extreme dislike for the Mario Bros., due to their constant intervention in the plans of the Boo leader and others of his kind, especially towards Luigi. He shows a bit of a snarky side in Dark Moon when he confronts Luigi with a speaking line "Remember when you trapped me for all eternity in a painting? Good times.". Lastly, King Boo has a distinct cackle, which is significantly lower in pitch than other Boos.
Personality[]
Luigi's Mansion[]
King Boo is notably darker in the Luigi's Mansion series than in other games. He was initially much fairer in his rule, going out of his way to save a high-ranking Boo and generally acting fond of his own troops. He despised the Mario Bros., so he plotted to get rid of them by capturing Mario and then tricking Luigi so he could store them both into paintings. This grudge also extends to Princess Peach and her Toad Retainers in the third game, despite them having nothing to do with his imprisonment. He also hates Professor E. Gadd since his Poltergust is only the thing that can harm him.
In the sequel, all of King Boo's altruistic traits have been rendered null. After his first defeat, he started to loathe Luigi even more than Professor E. Gadd and Mario, to the point of conducting an elaborate revenge scheme involving shattering the Dark Moon and causing the benevolent ghosts to fly out of control. King Boo is consumed by revenge and notably cares little for his troops, experimenting on the ghosts he enslaved and broke into submission and treating his Boos as common casualties. It reaches the point where he willingly opens a portal to the ghost's homeworld with the intent to destroy the universe as an act of spite. He is noticeably less comedic and more openly cruel to Luigi, as well as sadistic, clearly relishing the terrified Luigi's pain with his mind games.
In Luigi's Mansion 3, though his plans are far smaller in scale compared to the previous game, King Boo seems to be even more determined to achieve his vengeance, sadistically taunting Luigi over the capture of his friends and family while becoming visibly infuriated by his forces' inability to stop him. Despite being freed by her, he shows no affection for Hellen Gravely or her efforts to impress him, openly stating that he wasn't confident that her plan would work when confronting Luigi, refusing to give her the opportunity to make up for her shortcoming and later disregarding her entirely for her failure upon her capture.
He eventually becomes fed up with relying on other ghosts to do his dirty work, deeming them all as useless, and instead decides to forego carefully laid out plans and traps in favor of tackling his enemies directly. During the final battle, he focuses himself entirely on removing his opposition to the point where he is willing to trap The Last Resort and everything around it inside a painting simply to get rid of Luigi. Overall, this version of King Boo is a purely evil spirit who disregarded any care he initially had concerning his subjects.
Powers and Abilities[]
Strength: King Boo is able to send heavy balls of a single load to the ground to fly and, during the events of the first game, pull Luigi around the rooftop like battlefield whilst being sucked up by the Poltergust 3000.
Ground Pound: King Boo's primary attack during Luigi's Mansion: Dark Moon where he pulls off a variant of Mario's Ground Pound attack by flying up and hitting the ground hard enough to generate shock waves on concrete which stun Luigi upon contact.
High Intelligence: King Boo is much more intelligent than the rest of his race. He was able to set up complex plans as well as deceive and manipulate Luigi many times.
Dark Magic Manipulation: Using his crown, King Boo can create dark magic to make anything appear or happen.
Flight: As with all Boos, King Boo is capable of self-propelled flight.
Teleportation: King Boo can make himself fade out of existence and fade into existence at will in a different location.
Portrait Entering: King Boo can enter paintings at will and seemingly escape from them at will, although he cannot do this after escaping. The only reason that he was able to escape was because of Boolossus before the events of the first game, because E. Gadd sold his painting between the two games, and because of Hellen Gravely during the prologue of the third.
Conjuring: King Boo is able to conjure up anything from nothing; like an entire mansion or a painting.
Fire Breath: King Boo is able to spit blue flames from his mouth.
Pyrokinesis: It is also shown that he can shoot fireballs from his crown.
Painting Imprisonment: King Boo is able to trap people in paintings; as he did with Mario three times, Professor E. Gadd, the Toads as well as with Peach. He does this by firing an energy blast from his crown and shooting the enemies into a blank painting.
Power Enhancement: King Boo is able to increase his own powers, whether with the presence of other Boos or with the jewel on his crown.
Power Gust: King Boo's most powerful "attack" in Luigi's Mansion, which he does when Luigi tries to enter his Secret Altar with the key from Vincent Van Gore if less than 40 Boos have been captured. He will call upon his minion's power and summon a massive gust of wind strong enough to launch Luigi back to the foyer, though how this occurs is unclear since the screen fades out when he's flying away and fades back in to Luigi recovering in the Foyer.
Duplication: King Boo is able to duplicate himself, into two, three or more copies.
Illusions Creation: True to his title as the "master of illusions," King Boo is able to create realistic illusions.
Ergokinesis: King Boo can manipulate energy.
Energy Blasts: King Boo, from his second grown onwards, can fire a massive purple beam of energy from his crown which was strong enough to shatter the titular Dark Moon in Luigi's Mansion: Dark Moon with one blast.
Electrokinesis: King Boo can control lightning such as when, during his battle during the second game, he he can summon purple lightning to strike certain squares indicated by them glowing. This appears to be the answer to Bowser's pyrokinesis, though it is also shown that he can use pyrokinesis as well.
Portal Creation: A charged up lightning blast from King Boo's crown was able up a massive portal during the penultimate level of Luigi's Mansion: Dark Moon, leading into the final "area" of the game, although a massive influx of ghosts prevents Luigi from immediately following. He seems to have lost this power following the destruction of his second crown.
Ghost Summoning: After the defeat of Big Boo in the penultimate mansion in Luigi's Mansion: Dark Moon, King Boo summoned a plethora of ghosts to invade this realm which would have torn it asunder had they not been stopped by Luigi.
Size Change: King Boo has shown himself to be much taller in Luigi's Mansion: Dark Moon than in Luigi's Mansion which he does at will after every time Luigi lands a hit on him as an extra segment in that game.
Technopathy (possibly): King Boo may have intercepted Luigi's teleportation, but the process for doing so is unknown.
Telekinesis: King Boo was to destroy E. Gadd's laboratory, levitate E Gadd and the Toads and then throw them into a painting during the climax of Luigi's Mansion 3 using just the power of his mind.
Mind Control: In Luigi's Mansion 3, King Boo revealed that he was controlling the Ghosts with the jewel on his crown.
Weaknesses[]
Bowser Suit: In Luigi's Mansion, King Boo is completely helpless outside of his Bowser Suit and will be helpless for a short time outside of it. However, once he gets below 200 HP, the suit's head will fly around and fire ice breath at Luigi to freeze him in place and leave him open to further attacks and give King Boo a chance to re-enter the suit.
Ground Pound: Ironically, King Boo's main attack in Luigi's Mansion: Dark Moon was also his undoing since he would project red spikes around the area to roll around as the arena tilts and he unleashes his attack. Coaxing him into hitting one of the spikes will damage him and cause the giant segment before restarting the fight with him having less health.
Spicy Food: King Boo hates spicy things, as throwing an jalapeño pepper in his mouth will set his tongue on fire and make him vulnerable.
Theories[]
King Boo and Bowser[]
Many fans speculated due to the Bowser Suit that King Boo used in his first battle against Luigi, as compared to the other mechs in the Mario universe, this one looks quite realistic. As the Mario universe has no set timeline, fans say that it is possible for Bowser to get killed and King Boo to be inhabiting his corpse. As the last game before King's debut was Paper Mario set in Japan as Mario Story, people say that one of the ghosts in the first mansion is reading Mario Story, which can be a historical book. Also, fortune-teller in the mansion exclaimed that King Boo could possibly revive Bowser, which means that King Koopa was already dead. There are several visions of the situation:
King Boo revives Bowser and takes his place as Koopa King, so in future games, Bowser gains supernatural abilities to stay alive even when burned to the bones like in New Super Mario Bros. with his Dry Bowser form. Then, King Boo which we see is actually just a Big Boo with a fancy crown, imitating King Boo. This can be canon due to the blue supernatural fire of Bowser, his Dry Bowser form (which also explains that regular Boos inhabit Dry Bones and are confused, when the player beats them only for Boos to return into skeletons), and the gold portrait of King Boo, showing him and Bowser having a confrontation.
King Boo revives Bowser and they make an alliance against Mario Bros, so King Boo is able to revive Bowser anytime when he gets killed and takes his body until Bowser recovers. This version means that King Boo looks like a regular Big Boo because of the loss of his enchanted power-crown, which gives him incredible battle powers and creepy look. This can be canon due to the pose of Bowser in the portrait, like having sleep before King Boo inhabits him, and also a gold portrait of King Boo, showing his confrontation with Bowser.
King Boo and Bowser are one and the same person. After his death, Bowser turns into a ghost, namely Boo, but still has some of his magic powers, which allowed him to bow Boos to his will. Then, he recreates his body (or creates a very similar mech) to inhabit it. However, he was unable to fully recover, so he traps Mario, though fails in capturing Luigi. This theory provides a thought of Boo-Regent like the one in the first variant. This can be canon due to Bowser having a good relationship with Boo and also quote of King Boo of Mario "giving him many troubles in the past". Also, this can be considered canon, as Bowser still has powers to be revived, as it is done not only by himself, but by Bowser Jr., Koopalings, and Kamek on several occasions.
That the Bowser fought in Luigi's Mansion is actually a powerful illusion created by King Boo. In Luigi's Mansion: Dark Moon, Boos are seen sealing Toads inside portraits and using "Spirit Balls" to make objects invisible. These paranormal phenomenons are referred to as illusions by Professor E. Gadd and King Boo is referred to by him as the “master of illusions” much later in the game. It is likely that the previous game's final boss fight was some sort of illusion Luigi was trapped in and had to fight his way through in order to save his brother. (Perhaps the same could be said for the titular fake mansion itself.)
Two King Boo's[]
There are fans who believe that there exist two King Boos in the series, and that is due to King Boo's appearances. For example, after King Boo's first appearance in Luigi's Mansion, King Boo later on made his second appearance in Mario Kart Double Dash!! which had his design changed to him being a regular Big Boo with a golden crown. This new design was used for the rest of the Mario games ever since, until Luigi's Mansion: Dark Moon came out where his original appearance from Luigi's Mansion came back. This led some fans to believe that the King Boo from the Super Mario series wasn't the same King Boo from Luigi's Mansion.
Although King Boo's appearance may be different because he is angry, this would be in line with the appearance of Mad Boos and Mad Big Boos from Super Princess Peach, which have similar glowing eyes and a similar shadow around their eyes. It also fits since King Boo is generally angrier in the Luigi's Mansion series than he is in other games: in the first game due to E. Gadd capturing Boolossus and some past meddling of the Mario Bros. in Luigi's Mansion: Dark Moon and Luigi's Mansion 3 due to Luigi meddling in his personal plans (those unaffiliated with Bowser) multiple times.
This would mean that King Boo's design that first appeared in Mario Kart: Double Dash!! is his default state of being, and there is also some support for this. In Mario Superstar Baseball, it is said the gold crown he has in that design is his trademark one: "The king of the Boos. The golden crown is his trademark, and while he looks similar to other Boos, it's obvious that he's much larger than the others."
In Mario Kart Tour, both King Boo's appear in both designs appear and are considered alts of the same character with the same emblem and everything. Even characters that are evidently the same, like Cat Peach, Baby Peach and Peach, have different emblems at times.
Beyond this, it is also noteworthy that in Mario Superstar Baseball, King Boo has bad chemistry with three characters: Luigi, Baby Mario and Baby Luigi. The bad chemistry with the babies may be riffing on the fact children are afraid of ghosts, but the bad chemistry with Luigi suggests a specific reference to the Luigi's Mansion series which would once again indicate both designs are the same character. In the sequel, Mario Super Sluggers, he additionally has bad chemistry with Mario, which makes sense given his anger towards Mario in Luigi's Mansion and his multiple kidnapping attempts.
Quotes[]
Luigi's Mansion series[]
“
What's on his back...!? It's... E. Gadd's Poltergust 3000! Everybody SCRAM!!!
„
~ King Boo's first word of dialogue
“
White gloves! A cute little moustache! Soft shoes! How did you get out of my...? ...Huh? Wait just a second... Your clothes are... green... Hey, you must be Luigi! Whoa, you had me a bit confused for a moment there! What? You want me to release Mario? Riiiiight. No, no, no. I will not give up my favorite decoration. I like Mario just where he is. Hey, so what's that you got there? A Poltergust 3000?! Uh oh! What should we do, Boos? Good idea, guys! All Boos in this area, gather your strength! We'll blow him away!!! ... We'll take a big Boo breath... and blow you away!!
„
~ King Boo
“
Aahh, I could just stare at my Mario painting for hours! It's true what they say about fine art...it takes utterly refined sensibilities to truly appreciate it! The way you plead for help, Mario... I find it so...satisfying. Perhaps that is merely because I remember how much trouble you've caused me in the past. Seriously, though, who would actually believe that mansions get given away in contests?! Talk about stupid! What do they feed you Mario brothers anyway...gullible soup? Your brother came all this way just to get turned into a painting... [chuckles] It's just terrific. However, this Mario painting looks lonely... I must have a Luigi painting as well! Then my gallery will truly be complete! [chuckles] I am not afraid of you, fool! I fear only that infernal Poltergust 3000 you carry on your back! Stupid machine! But I am a KING among Boos! I swear it... I shall fear no mere house-cleaning device!!! I must say...I despise the way you SHWEEERRPP-SHLOOOOP-WHOOORPP-SHLEEEOOORG-vacuumed up all my friends! Don't imagine that I'll flee... I'll fight you like a true Boo! Now join your brother... INSIDE THE PAINTING!!! [maniacal spooky laughter]
„
~ King Boo confronting Luigi for the first time in Luigi's Mansion
“
Mwahahaha! Now what do we have here? Why, if it isn't my old pal Luigi! Or is it Baby Luigi? I can't tell the difference. Hey, remember that time you trapped me in a painting for all eternity? Good times. But guess what? I GOT OUT! And now I'm painting the town RED! Yes, it was I who broke the Dark Moon! This power-enhancing jeweled crown of mine made it easy. And now that all the ghosts of Evershade Valley are under my control, it's time to take my rightful place as supreme ruler of your world! You, that annoying scientist, and all your friends will look great hanging from the wall of my throne room! AAAAAAHAHAHAHA!!!
„
~ King Boo confronting Luigi at the end of Luigi's Mansion: Dark Moon.
“
Gwahaha! If it isn't my good friend, Luigi! It's me, your ol' pal KING BOO! Y-You're not telling me you FORGOT ME!? Well, I certainly haven't forgotten YOU! You, that ratty vacuum cleaner, and that stinky old geezer who made it! I haven't forgiven what you did to me, so I've led the ghosts here in an uprising! But you... you and that DISGUSTING machine just SHLEEEERP-SHWOOOOOP-SWHLOOORPSHLOOOORP-SHWEEEERPed them all up! You think I'll let you get away with that!? You're going down this time, Green 'Stache!
„
~ King Boo confronting Luigi in Luigi's Mansion Arcade
“
Mwah ha ha! Surprise, Luigi! It's-a me, King Boo! That old coot had me locked up tight in his lab... But guess what? I GOT OUT! The hotel owner here was just dying to meet me, so she busted me out. Pretty lucky, huh? Anyway, I didn't think you'd actually show up here. I was ready though, just in case. In fact, my vengeance is nearly complete! What do I mean by "vengeance"? Glad you asked! I'm trapping you and everyone in your little vacation party...in frames! Awww, there there, Luigi. It'll all be over soon. It's time for a family reunion! BOO-YA!
„
~ King Boo revealing himself and Luigi's captured friends in Luigi's Mansion 3
“
Mwah ha ha! Take THAT! Oh, and there's one more frame, of course. I saved it especially for you! Stay right there and put on your best terrified face, Luigi! This is game over!
„
~ King Boo preparing to trap Luigi
“
Mwa ha ha! how brash of you to come and face me, Luigi! You should have just run away while you had the chance! But instead you stayed and fought all the way up here to oppose me? How foolish! You may have made your way through the hotel using E. Gadd's frustrating inventions to suck up all the ghosts in your path... You were all SHWEERRPP-SHLOOOOP-WHOOORPP-SHLEEOOORG! Ahem. Anyway, just because you vacuumed up all of those ghosts doesn't mean you can take me on! It doesn't matter that you beat the hotel owner... Hellen Gravely! Ooooooo! She let all your friends get away! It's so frustrating when you trap something in a painting and it gets out, you know? Arg! Hellen Gravely... All those ghosts... Useless! I have to do everything myself! I'm sick of this! No more mercy for you, Luigi! No more tricks—no more carefully laid plans! Now it's time for raw King Boo gusto! You're all going in a painting! An ensemble portrait is your fate!
„
~ King Boo furiously declaring his hatred of Luigi and preparing to trap him and his friends.
“
Mwa ha ha! Serves you right! Just a few left. Go on! Join them! My painting must be complete! Sorry to keep you waiting. Are you ready? I don't care!
„
~ King Boo preparing to trap Mario, Princess Peach and Luigi after capturing Professor E. Gadd and the Toads.
“
...Hmm? One-two-three-four-five-six-sev—WAIT! There should be seven! Who's missing!?...Luigi! What are you doing over there?! UGH! That's it! I'm sick to double death of you! You want to fight me? FINE! Let's go, Luigi! This is the end for you, once and for all! HERE I COME!
„
~ King Boo's last words before his final battle with Luigi.
Super Mario 64 DS[]
“
Big Boo's Haunt. Eee hee hee...There are no exits. You may as well wander in here forever...Listen carefully. Can you hear me? If you find me, you're history. Eee hee hee...
„
~ The Sign Post, written by King Boo
“
Eee hee hee! I am Big Boo, the spookiest of all the spirits! I locked up the whimpy green moustache man. And I'll do the same to you! Eee hee hee! Since I'm a ghost, I can turn invisible in the mirror's reflection. You'll have to attack me from behind to defeat me. But you'll die of fright before that ever happens! And then you'll be one of us!
„
~ King Boo before his first clash with Mario
“
Eee hee hee... I am Big Boo, the spookiest of all the spirits. I love scaring wimpy humans. Eee hee hee... You'll never sneak behind me!
„
~ King Boo before the next challenge with Mario
“
Eee hee hee! I am Big Boo, the ghastliest of all ghosts! What the...? I thought I locked you up...Well, never mind. Now I'll really creep you out! You can't escape...Eee hee hee!
„
~ King Boo's clash with Luigi, although Luigi is free
“
Eee hee hee! I am Big Boo, the scariest of the spirits. Eek! What's this?! Your face... It would even scare a ghost. How horrible! You've got it backwards... I do the scaring around here! All right, now I'll put some real fear in that frightening face of yours! Eee hee hee!
Eee hee hee! You can never really kill a ghost! We always come back! See you again. Eee hee hee!
„
~ King Boo if he is defeated by Mario
“
Eee hee hee! We ghosts always rise from the dead. I just love the look of terror on your face! In fact, I live for it! Eee hee hee! See you soon!
„
~ King Boo if he is defeated by Luigi
“
Augh! The scariest one wins, and your face is flesh-creepingly frightening. Good thing I don't have any flesh! Eee hee hee! This is not the end. See you again.
Right here, fools! Right under your noses! Now bring me my 10 coins!!
„
~ King Boo's introduction in Mario Party 8
“
Horrifying! You got 2 Stars! I'll never live this down! I'll just slip away quietly...
„
~ King Boo's defeat, after the player got two stars, Mario Party 8
“
Well, well, well! Aren't you a bold one to come face-to-face with me, King Boo! I'll steal a Star from each and every one of your unsuspecting opponents! Or I can just steal coins if you prefer those instead. Now, what'll it be?
„
~ King Boo in Mario Party Superstars
“
I hereby decree that (character) will win, and the king's word is absolute! (character) has this in the bag, and don't you dare question me! Mwah ha ha!
„
~ King Boo in the last 5 turns of events.
Other[]
“
Booo hoo ha! HEY! You defeated Bowser Jr.! I wondered who would win, so I made myself invisible and watched the whole thing. You booooth look like benchwarmers to me!
„
~ King Boo in Mario Super Slugglers
“
Hey! You there! What you got there? Huh? ...HEY! That's a Boo, isn't it? Yeah! It is! Aw... Little Boos are so cute! But I don't want to see him riding pine! Put him in a game, yeah?
„
~ King Boo being counted in, Mario Super Slugglers
“
Look at this little scrap. Friend of yours, is he? Well, if you like your friend, you better stop attacking me! Now, don't go thinking it's OK to attack my little minion either. Who knows what could happen if he dropped your little friend there... You got that?
„
~ King Boo in Mario and Luigi: Paper Jam
“
Heh heh heh! I saw that Alpine Downhill event of yours yesterday! Looks like you need to take a lesson in speed from ME! And that lesson starts today! I challenge you to an Alpine Downhill match! Hee hee hee!
„
~ King Boo's rival appearance in the Wii version of Mario & Sonic at the Olympic Winter Games.
Audio Samples[]
King Boo's Laughter[]
Sound Files
File
Description
King Boo's Fire Breath (Super Mario 64 DS only)[]
Trivia[]
King Boo's quote, "I don't plan to give up my favorite decoration. I like Mario where he is." is a quote derived from Star Wars VI: Return of the Jedi, when Jabba The Hutt said, "I don't plan to give up my favorite decoration. I like Captain Solo where he is."
Luigi is canonically the only Mario character to fight King Boo more than once, due to him being his arch-enemy (excluding spin off games like Mario Party).
In the English version of Super Mario 64 DS, King Boo was called Big Boo due to a localisation error.
In the Mario Party 9 Sound Test, there are two voice sounds with the name "King Boo's Entrance"; one is King Boo and the other is actually Boo.
The Japanese, Dutch and Korean names for King Boo use the English word for king, instead of a word in their own dialects.
Although he commands a large band of Boos, not all Boos call King Boo their leader, with some Boos working directly for Bowser, and many others living peacefully with the other denizens of the Mushroom Kingdom, either independently or as part of a small band of Boos led by Lady Bow.
In the pre-release version of Luigi's Mansion, King Boo resembled Big Boo from Super Mario 64.
King Boo's design in Super Mario Sunshine is a prototype of his Mario spin-off titles appearance.
King Boo's design in the Mario spin-off titles debuted in Mario Kart: Double Dash!!.
King Boo's Luigi's Mansion appearance also made an appearance in Mario Kart Tour.
He makes a cameo in The Super Mario Bros. Movie during Bowser's wedding. In the movie, he looks more akin to how he looks in the mainstream series than how he looks in the Luigi's Mansion series.
Interestingly, he is one of the wedding's only two attendants (the other being King Bob-Omb, who was sleeping) who didn't attack Peach after she froze Bowser, which, if there is ever a movie based on the game "Luigi's Mansion", might be a foreshadowing of his possible betrayal of Bowser.