Mr. L

"The Green Thunder strikes like lightning!"

- Mr. L

Mr. L, also known as The Green Thunder or The Mysterious Mr. L, is a brainwashed version of Luigi who makes his only appearance in Super Paper Mario, serving as an acolyte of the evil Count Bleck. According to The InterNed, Mr. L's theme song is titled "Mr. L, Green Thunder". He is a major antagonist and eventually becomes the game's final boss, Super Dimentio by fusing with Dimentio and the Chaos Heart. Before turning evil, Luigi tries to stop Count Bleck from using the Chaos Heart; however, after being trapped in Castle Bleck, Luigi gets brainwashed by Nastasia, ultimately turning him into Mr. L.

In the Light and Dark Prognosticuses
It is implied several times that Luigi is the "man in green", referenced in both the Light Prognosticus and the Dark Prognosticus. Both of these two books state that this man in green and his affiliations will determine which prophecy is true. As such, it can be taken that, if Luigi were to have stayed Mr. L throughout the course of the game, the Dark Prognosticus would have been fulfilled and all worlds would be destroyed, making the end of Luigi's hypnotizing and evil ways integral to Super Paper Mario. Dimentio additionally states that the Dark Prognosticus mentions Luigi as the ideal host for the Chaos Heart.

Early history (as Luigi)
An unconscious Luigi is seen among the audience of Bowser and Princess Peach's wedding in Castle Bleck's wedding hall. As Luigi gains consciousness during the events of the forced marriage, he attempts to save Princess Peach from Count Bleck and his associates, but ends up only provoking the Chaos Heart. The Chaos Heart was later secured by Count Bleck shortly afterwards.

Luigi is soon warped to a corridor of Castle Bleck. He meets an unnamed Goomba and another named Gary that trick him into helping them escape the castle. Luigi makes an attempt at saving his group and Peach, but ends up coming to a dead end, where he is promptly surrounded by Nastasia's forces, who hypnotizes Gary, causing the unnamed Goomba to join with Count Bleck's side. Though Luigi's fate is not explicitly seen, he is shown to be tackled by the troopers and is seemingly about to be hypnotized by Nastasia (foreshadowing Mr. L) just as the scene is cut.

Mr. L's encounters
Mr. L himself is first seen in the Whoa Zone, where he kicks Squirps in a room before the statue of Squirpina XIV and the resting place of Outer Space's Pure Heart. After quickly trash-talking the three heroes, he engages them in a brief mini-boss battle with them. During this battle, he is able to heal himself using Shroom Shakes, but the heroes can use Thoreau to steal these shakes for themselves. After his 40 Heart Points are depleted, Mr. L falls to the ground and compliments the heroes on their battle skills, but quickly summons his mechanical "brother", Brobot, to finish them off. With the effect of the screen ripping in half, the characters are all transported to the depths of space, where Mr. L and Brobot battle them above what flipping would reveal to be a green, vector-graphic-filled mountainous expanse. Using Squirps's Squirp Squirt Beam, the heroes destroy Brobot and the villain plummets back down to the ground. With one last boast of a future ability to prevail over the heroes, Mr. L escapes, allowing them to obtain the Pure Heart.

Mr. L next appears in the Castle Bleck intermission after Chapter 4, the beginning of which focuses on his "new-minion orientation." Mr. L is shown here to be boastful even around fellow minions of Count Bleck, seeing his comrades as weaklings and "junior minions". O'Chunks and Mimi react negatively to this, with Mimi noting to Mr. L that he too, had been, defeated; Mr. L's response is that he was "merely scouting" Mario, and would soon defeat him. With a cry of "L-ater!", Mr. L jumps off to Castle Bleck's unseen repair bay. Count Bleck later quotes a section of the Dark Prognosticus stating the potential of the man in green, whom Count Bleck reveals is Mr. L.

In the intermission after King Croacus IV's defeat, Mr. L expresses a longing to make another attempt at destroying the heroes with his newly-repaired and improved Brobot. However, Nastasia relays a command from Count Bleck for the minions not to attack, and Mr. L thus could not carry out his plans. Mr. L then proceeds to whine, until Dimentio, encouraging the fulfillment of his own gambit, appears and convinces Mr. L and Mimi to attack anyway in saying that Count Bleck would be pleased if they were to end the heroes' games.

As laid out, Mr. L encounters the heroes once again in the obliterated Sammer's Kingdom, where he takes the stone Pure Heart of Sammer's Kingdom for himself and engages the heroes in battle along with his improved Brobot. After he is beaten, he flees, allowing the heroes to obtain the stone Pure Heart.

After Mario's team leaves the World of Nothing, Mr. L is shown in a cutscene where he ponders his inability to beat the heroes to himself. Shortly afterward, Dimentio appears, attempting to destroy him on the apparent basis that he, having lost once more, would be unable to show his face to Count Bleck (in actuality, Dimentio plans to undo Mr. L's hypnotism and reunite Luigi with Mario so they could help him destroy Count Bleck; he also uses his ambiguous help to Mario as a basis to convince him to join him in the battle against Bleck). Dimentio successfully destroys Mr. L, sending him to The Underwhere.

Super Dimentio
By destroying him, Dimentio cures Mr. L of Nastasia's hypnosis and reunites him with Mario (at which point Mr. L's theme plays). Luigi joins the heroes in their quest, fighting alongside Mario, Princess Peach, and Bowser, who are eventually able to defeat Count Bleck. However, prior to this momentous victory, Dimentio had planted a Floro Sprout seed in Luigi's mind that grows into an adult Sprout, just as he is ready to finish the remaining three heroes off so he can destroy all worlds and create his new ones. Although Luigi notices and tries to resist his brainwashing, Dimentio recreates Mr. L.

Making way for a new creation, Dimentio orders Mr. L to move into position and merges him with the Chaos Heart in a hole resembling the Void. While one with the evil heart, Mr. L becomes the more Dimentio-themed Super Dimentio, a gigantic clown-like puppet bearing some resemblance to a twisted Luigi. Seemingly eliminating the new Mr. L's sentience, Dimentio takes control of Super Dimentio, challenging the remaining heroes. With help from Count Bleck and his minions, the heroes are able to summon the Pure Hearts to destroy Dimentio and the Chaos Heart, bring back Luigi and finally erasing his hypnosis and brainwashing.

Super Smash Bros. Brawl
In Super Smash Bros. Brawl, Mr. L is mentioned under the name Mister L in Paper Luigi's trophy. The sentence states that Luigi only has a rumored "close relationship" to Mr. L and misattributes Luigi's brainwashing to Count Bleck. However, this could have been intentionally done to not spoil the ending, as Mr. L is not revealed to be Luigi until the end of the game.

Super Smash Bros. for Wii U
Mr. L makes a cameo appearance as a trophy in Super Smash Bros. for Wii U. It can be unlocked by playing solo Cruel Smash as Luigi and surviving for one minute.

Super Smash Bros. Ultimate
Mr. L appears in Super Smash Bros. Ultimate as an Attack-type Advanced-class primary spirit that takes up two slots. The spirit has great power at the expense of granting the user weakness to water-type attacks. In World of Light, the Mr. L spirit is found in the Lost Woods portion of the Sacred Land sub-map in the Dark Realm. In the spirit battle, the player faces Luigi (in his Waluigi-based palette) on the Luigi's Mansion stage, which is fog-covered unless a fog immunity support spirit is equipped.

Super Mario-kun
Mr. L appears in volume 37 of Super Mario-kun. Unlike in the game that inspired this volume, characters are not fooled by Mr. L's disguise, to the point where Bowser makes fun of Mr. L for being a poor disguise. As Mario and co. grab a happy flower, Mr. L's evilness goes away and reverts to Luigi.

Physical appearance
Mr. L strongly resembles Luigi, though he is dressed in a black jumpsuit that strangely retains his former overalls' large buttons. He also wears a green bandana around his neck. His cap has a black background and reversed "L" instead of the normal white background and normal "L". Over his face is a black mask which seems to effectively hide his identity; this mask makes his eyes and eyebrows appear white. His gloves and shoes are dark gray. Mr. L, unlike standard Luigi, is shown to have a belt.

It may also be worthy of note that official artwork depicts Mr. L's mustache as black whereas Luigi's Super Paper Mario artwork gives him a brown mustache. In game, however, both forms' mustaches are brown.

While it is somewhat obvious that Mr. L is a brainwashed Luigi to the player, the other characters in Super Paper Mario do not make the connection, though they do feel like they know him in some way. This is done for both comic relief, and to facilitate the game's developing storylines.

Personality
Mr. L is very cocky and is always praising up himself, a stark contrast to the chicken-hearted, reluctantly brave Luigi. He thinks highly of himself and is not slow to reveal it, often trying to openly annoy other in-game characters. He has a sophomoric belief in his often-boasted-of abilities, as he is very shocked at his failures as their series begins. He is very daring, and as such reveals an attraction to Princess Peach and jealousy of Mario's jumping ability. His loyalty to Count Bleck, while very deep (with him greatly longing to impress the count), is never explained, and he seems to care little about the expenses worlds would pay had Bleck's plans realized, something that seems to be the result of Nastasia's brainwashing.

Mr. L has two catchphrases: "L-ater," which he continuously proclaims when exiting Castle Bleck, and "Have at you!", his battle cry. He has become well-known for his introduction (actually done only once in the game, not counting a shortened version featured in his new-minion orientation), in which he is given a repeated, blurring closeup as he spins around and strikes a pose, shouting "MR. L!" as rotating green rays are emitted from his body. He also has a knack for nicknaming, referring to Mario as "Mr. Jumpsallthetime," Peach as "Ms. Alwaysgetskidnapped," or Bowser as "Mr. Getsfoiledallthetimebytheredguywiththemoustache" during their first confrontation; this may imply that he still retains some of his memory from when he was Luigi, as he subconsciously recognizes who Mario, Peach, and Bowser are. He also nicknames himself "the Green Thunder".

Dimentio's Mr. L seems to have no personality differences from Luigi, if he can be said to have any personality at all. Super Dimentio, however, does give a few of Mr. L's cries, such as "GREEEEEEN!" and "L-POWER!".

Powers and abilities
Mr. L's abilities are largely the same as those of Luigi. He runs and jumps just like Luigi, with low traction and a high jump. He also has the ability to super jump, a move that Luigi can use much later in the game, which he uses to attack Mario, Peach and Bowser. He can also use Shroom Shakes, like the other heroes.

However, Mr. L has some skills that Luigi does not, or merely has not yet shown, namely his inventiveness. Though Luigi has been known to have run a mechanical-themed board in the Mario Party series, his mechanical skills haven't been consistently shown to match that of Mr. L. Mr. L has the intelligence to build, upgrade, and pilot his own robot, which he calls Brobot, throughout the course of Super Paper Mario, pioneering the art he refers to as brobotics.

Tattles
First Battle: "That's Mr. L. This new hire of Count Bleck's a real mystery man... Max HP is 40. Attack is 3. He uses his high jump as a weapon... And that powered-up super jump is quite...super... He has no other outstanding features of note. And why does he remind me so much of Mario...?"

Brobot: "That's the Brobot. This super robot is one of Mr. L's creations... Max HP is 255. Attack is 4. Defense is 3. Defense against fire is 6. It is loaded with different weapons that allow it to attack from any angle... Just try to avoid its attacks and use Squirps's beam when you get a chance... And try to grab a few Choco-Bars that float by..."

Brobot L-type: "That's Brobot L-type. Mr. L pulled out all the stops to make this one... Max HP is 64. Attack is 5. Defense is 4. Defense against fire is 8. Most of its moves are the same, but it can now use its hands or tackle you... He seems to be weak to explosions, so try using Boomer on his feet... You remember that after setting a bomb, you can press 1 again to set it off, right?"

Super Dimentio: "That's Super Dimentio, a freakish blend of Dimentio, the Chaos Heart, and Luigi. That monstrous body has immense power... Max HP is 200. Attack is 6. Concentrate attacks to the head. You'll have to climb those platforms to reach the head to attack. This is truly the final battle... Winning is the only option..."

Quotes

 * "Oh, me? Just one of Count Bleck's more promising minions. The Green Thunder... MR. L!"
 * "Just because you're in red doesn't mean you're strong. Have at you!"
 * "Ooh, the evil king of all charlatans! Do I look scared? Have at you!"
 * "No one's coming to save you this time, dearest princess! Have at you!"
 * "Hey, Mr. Jumpsallthetime! NOW we'll see who's the better jumper!"
 * "Hey, Mr. Getsfoiledallthetimebytheredguywiththemustache! I'll foil your FACE!"
 * "Hey, Ms. Pink n' Frilly! Try not to get kidnapped before I defeat you! Have at you!"
 * "Hey, Ms. Alwayskidnapped! I'll kidnap your FACE!"
 * "I uh... got to go deflavorize the Brobot's uh... Flavorizer."
 * "Hey there, butterball!"
 * "Hey, King Incompetent! I'm gonna hatch an evil plan on your FACE! Have at you!"
 * "I was just scouting him, dear. Next time, he will be mine!"
 * "But Brobot craves his daily smash! I can't just loiter here! There's no action!"
 * "L-ater!" - Mr. L
 * "Looks like your Pure Heart thing got broken. I guess Pure Hearts can't handle the end of the world. Heh. Whatever, I'll swipe it just for kicks."
 * "Meet my new friend... BROBOT L-TYPE!"
 * "Not a funny joke, Dimentio... If I wanted to laugh, your face is inspiration enough!"
 * "Dimentio... No..."

Trivia

 * Mr. L shares many similarities with Lord Crump from Paper Mario: The Thousand-Year Door, in that both of them are arrogant underlings of their games' primary antagonists, both command massive mechanical creations as well as updated versions of them, and both of them don disguises that are fairly easy to see through by the player, so much so that Mario's partners often lampshade it.
 * Mr. L's self-given nickname could be a reference to Luigi's Thunderhand ability from Mario & Luigi: Superstar Saga.
 * Shadoo's first form (Dark Luigi) looks identical to Mr. L instead of normal Luigi.