Mario & Luigi: Bowser's Inside Story

Mario & Luigi RPG 3 (tentative title, Japanese Mario & Luigi RPG 3!!!) is the third title in the Mario & Luigi series, for the Nintendo DS. It was confirmed on October 2 at the Fall 2008 Nintendo Conference, and was released on February 11, 2009 in Japan. Unlike Mario & Luigi: Partners in Time for the Nintendo DS, this game makes greater use of the DS's touch controls and microphone.

Plot


After the Mushroom Kingdom's citizens begin to fall victim to the mysterious "Metakoro Disease," Princess Peach calls a meeting, which is attended by Mario and Luigi. A new character, Yellow Star, has discovered the cause of the disease. As Peach is giving a meeting on its effects, Bowser breaks into the meeting. He is quickly defeated by Mario. Peach and Yellow Star use their powers to send him to Ekubon's Forest, and the meeting continues. Meanwhile, Bowser gets an item called a "Lucky Mushroom. In realty though, it is actually a "Vacuum Mushroom", which is a trap set by Fawful. It allows him to control Bowser's actions, and gives Bowser the ability to inhale everything. Bowser goes to Peach's meeting and inhales everyone there. While gloating about his victory, he mysteriously falls unconscious, and Fawful appears.

Mario reawakens alone inside Bowser's Body. Nearby, he finds Luigi and Yellow Star. The three of them set out to reawaken Bowser. They come across an exposed nerve, and attack it, which rouses Bowser. He discovers that he has somehow come to Gepū Cape. He sets out north, towards his castle. As he is leaving Gepū Cape for Musshība Beach, he is confronted by a mysterious voice explaining the concept of Chakras to him. A Chakra is a portal that allows him to quickly traverse the Mushroom Kingdom.

At Musshība Beach, Bowser hears a voice calling to him from a small island. He sees the famous block collector, Brirock. Initially reluctant to help, Bowser is convinced when Brirock offers him the Vacuum Block, an object that gives its user the capacity to use a powerful suction attack. After rescuing Brirock, Bowser must fight his missing pet, Blodog. At the north end of the Beach, Bowser comes across the Marine Pipe's Statue. Because it is dedicated to an ancient hero, Bowser begins to vandalize it. Unbeknown to to Bowser, Fawful's cronies have imbued it with the power of self defense, and it attacks him. After Bowser deactivates it, a stream of water flows from the statue. Drinking from it, Bowser inadvertently opens a path allowing the Mario Brothers to reactivate his fire breath, which is being blocked by the parasite Betarīno. He uses this rediscovered skill to continue northward, back to Ekubon's Forest.

In the forest, Bowser runs across some of his old troops. Fawful has trapped an army of still loyal Goombas in a cage. When Bowser frees them, they accompany him for the remainder of his time as a leader-in-exile, allowing him to use the attack Bokosuka Goomba. He also meets up with Heifā, Patabon, and Kurikkī, three former troops from his army. They are attempting to retake the castle using a Banzai Bill canon, but they don't have any ammunition. Bowser heads to a garden maintained by a Wiggler clan. Bowser finds a huge carrot, which he thinks may make a suitable replacement, but a local wiggler is infuriated when he removes it. The wiggler demands that he eat the carrot and battle him. Afterwards, it turns out that the wiggler happened to have a Banzai Bill at home. Bowser takes this and returns to the clearing where his troops are setting up the cannon. On the way, he is stricken with a horrible pain. The Mario Bros discover that the source of this pain is the hornworm-like Imounu, who is running rampant inside Bowser. After Imounu is defeated, she shrinks down to the size of Mario's foot and scuttles off. Exploring their current location, the Marios find Toadbert and unlock the Sliding Punch.

Bowser returns to the Banzai Bill cannon and fires his newly acquired ammo at his castle. Metaboss, a minion of Fawful who has been put in charge of the castle, is none too pleased with this. He lifts the entire castle up on rockets and flies it to Ekubon's Forest. He sets it down directly on top of Bowser, who is thoroughly unprepared for having a castle land on his head. The Marios travel to his Adrenal glands, and there cause a spike in Bowser's hormones. This causes Bowser to grow to almost the size of the castle itself. He engages it in battle, and is able to damage it significantly enough to force Metaboss into retreat. Bowser then returns to his normal size, and discovers that a path has been cleared through the forest during the fight. He continues north to the castle.

At the castle, he discovers that his subjects have been brainwashed by Fawful, who is hosting some kind of theater event in the castle later that day. When he arrives at the theater, he's informed that there is a special reserved seat for him. As the event goes on Fawful announces that they have a very special guest. Bowser's chair suddenly goes flying towards the stage, where he lands in a heap. Fawful tells the crowd that there's going to be a fight to the death between Bowser and Metaboss. A cage lowers, and they begin battling. After Bowser wins, a group of Boos escorts him to the winner's feast. Here, at the insistence of the boos, Bowser eats so much that he breaks through the floor with his weight.

While attempting to find a solution, the Mario Bros. discover Princess Peach. However, she is kidnapped almost immediately by Arukaroten. The Marios chase it to a dead end and rescue Peach. Peach informs them of Fawful's plan to steal the Dark Star, an ancient artifact held beneath Toad Town. However, Fawful uses an unknown machine to kidnap Peach. After using a treadmill and (literally) burning off some calories, Bowser sees a Bob-omb. He attacks it with his fire, but it quickly walks over to a much larger group of Bob-ombs and expodes, setting off a chain reaction that catapults Bowser to an Underground Tunnel beneath Gepū Cape.

Here, Bowser meets a clan of Monty Moles, who are digging a connecting tunnel to the Toast Town underground. When Bowser arrives there, however, he activates a trap and is knocked unconscious. The shock of the trap has knocked something loose inside Bowser, and the Mario Bros. discover a warp pipe out of their ally. They end up somewhere in the Toad Town underground, and begin looking for the Dark Star in hopes of securing it against Fawful. However, they are too late. Fawful takes it and heads for Peach's castle. Chasing after him, they are stopped at the castle gates by the Dark Star's power. They go to the local clinic to see how Doctor Kokino's research on the Metakoro Disease is going. However, while talking in Kokino's office, Bowser barges in and engages the Marios. After Bowser is defeated, Kokino tells the Marios that the three Star Vaccines are the cure for the Metakoro Disease. He explains that the first is held by Imounu, of Ekubon's Forest. However, Mario remembers that Imounu is no longer at Ekubon's Forest, so the heros set off in search of Imounu.

As soon as the Marios re-enter Bowser, they spot Imounu and begin to chase her. However, they are stopped when she runs behind a mysterious wall of green Boo Blocks. Meanwhile, Bowser is headed to Imounu's last known location, Ekubon's Forest. On the way, however, a large mechanized tower attacks Bowser. As earlier, Bowser grows to the size of the tower to fight it. After defeating it, Bowser enters the now-docile tower and climbs to its summit. Here he meets the ghost of Ibikki, the deceased owner of the tower. Ibikki explains the Boo Light Machine, a device he designed that can have various effects on Boos. By shining this light at Bowser's body, the Mario Bros are able to resume their chase of Imounu. When the catch up to her, she engages them in battle, revealing her true form as Sage Imounu. After her defeat, she gives the second Star Vaccine to the Marios.

Bowser meets up with Kurikkī, who reminds him that there's something like a Star Vaccine in the Bowser's Castle vaults. Heading there, Bowser is shocked to find that a railroad has been installed in the vault, and that Fawful's Gera Express is removing all the treasure within the vault. In an attempt to stop this, Bowser is crushed by the train. Thinking quickly, the Marios once again journey to Bowser's adrenal glands. The now-giant Koopa King quickly takes revenge on the train that stole all his treasure. Returning to the vaults, he discovers the safe that the Star Vaccine is stored in. However, he can't remember the combination for the safe. The Marios journey to his memory to search for the missing information. There, a strange creature scans the Mario Bros and creates doubles to battle them. After the Marios defeat their counterparts, the blue creature reveals that it is the guardian of the second Star Vaccine. It shows the Marios that the memory of the safe's combination has been damaged. After the Marios repair it, Bowser abruptly remembers the combination as a short poem. When he opens the safe, however, Kurikkī, Heifā, and Patabon shove him inside and lock the safe, stating that Bowser's reign is over, and that Fawful has placed a price on his head. Chippy advises Bowser to swallow the Star Vaccine, which he does. The Marios take it from his stomach and escape through the pipe to Toad Town.

Doctor Kokino tells the Marios that the third Star Vaccine is hidden somewhere at Musshība Beach. Journeying there, they discover a new area of the beach that they had never visited before. There they meet Chakran, the owner of the Chakras that Bowser uses to travel. He tells them that he is the third Star Vaccine's guardian, and that if they can defeat him, they can have it. They engage him in battle, but they can't do any damage. Running away, they go to Ekubon's Forest, where they search for the Attack Parts for Sweet Basket. After they find six of them, Mario is kidnapped by a Shokuchu. Luigi gives chase, and in a scene reminiscent of Super Mario Bros 3, Luigi is trapped inside a Shokuchu and must use it to traverse a field of thorns to rescue Mario. In the process, Luigi collects the remaining Attack Parts and completes Sweets Basket. Heading back to Chakran, the Marios use this new move to knock him over, and receive the third Star Vaccine for their efforts.

Mario and Luigi return to Doctor Kokino at the clinic. Taking the three star vaccines in hand, the doctor creates the Miracle Vaccine, the cure for the Metakoro Disease. It instantly takes on a life of its own, flying around the city and curing all those who are ill. Once it is finished, Mario and Luigi take it to the gates of Peach's Castle, where it destroys the barriers put up by the Dark Star.

After wandering the castle gardens for a while, the heroes come upon a huge mound of garbage. As Yellow Star wonders why it was left there, Metaboss comes in and activates a switch, causing the garbage to come to life and form the robotic Garakuta Monster. After being dealt enough damage by the Mario Bros, it begins to malfunction, running around wildly and freeing Bowser in the process. However, Bowser's long stay in the safe has caused him to fall unconscious, so the Marios set about waking him up. Heading through a nearby pipe, the Marios find themselves once more within the Koopa King. After a bit of searching, they come across Toadsworth inside Bowser's shell. He explains that from the shell, another latent ability of Bowser's can be activated. The shock of this is enough to rouse Bowser from his stupor, and he sets off in search of Fawful and the Dark Star.

Bowser finds Fawful and Metaboss watching a machine in which Peach and the Dark Star have been restrained. Fawful quickly grants Metaboss an ice-based powerup, sending him to attack Bowser. Metaboss' defeat causes his entire body to freeze, with cold air slowly being exhaled through his nose. Fawful absorbs the power of the Dark Star and escapes, while the Dark Star itself invades Bowser's Body. Mario and Luigi head to the only remaining unexplored sector of the body to find Dark Star. They catch up to it several times to find it absorbing Bowser's DNA. When it finally reaches a dead end, it confronts the Marios in battle. Although they win, the Dark Star reveals that the DNA it absorbed has allowed it to recreate Bowser's body and power for itself. It escapes from Bowser and from the room he's trapped in, which also gives the real Bowser the opportunity to escape.

Bowser finds Fawful in the conference room where he fought Mario earlier. The shadow power absorbed from Dark Star has caused Fawful to transform into Dark Fawful. Bowser fights Dark Fawful and destroys his body, but he survives as a ball of shadow energy. Dark Fawful escapes, but is absorbed by Dark Star. With Fawful's power, Dark Star becomes Dark Bowser and escapes through a hidden door.

Bowser finds Dark Bowser on a platform high above Peach's Castle, a knocked out princess at his side. Dark Bowser states his intent to rule the Mushroom Kingdom with an age of darkness, but Bowser replies that the Mushroom Kingdom is his country, and that Dark Bowser can't have it. They begin battling, and Bowser defeats Dark Bowser with ease. However, Dark Fawful revives Dark Bowser, fully healing him and powering him up. Bowser attacks Dark Bowser's Stomach, causing Dark Fawful to be ejected. Bowser quickly inhales Dark Fawful, and a battle begins in his stomach. In a battle somewhat reminiscent of that that they had with his old mistress, the Marios are forced to defeat the individual parts of Fawful's body before attacking his weak point, the Dark Star Core. After a difficult battle, Fawful is defeated, causing Dark Bowser to become unstable. Mocking him all the while, Bowser punches Dark Bowser until he can't take it any more and explodes, freeing the Mushroom Kingdom from the Dark Star's influence forever.

Within Bowser's belly, Fawful speaks to the Mario Bros. and Yellow Star. The Marios are shocked that he has somehow survived, but without a body or the power of Dark Star to sustain him, Fawful soon is no more, exploding in a cloud of black smoke. Without Fawful, however, the Vacuum Mushroom also ceases to be, meaning the inside of Bowser ceases to be the ridiculously cavernous space that it has been for most of the game. Almost immediately, all the various things Bowser had inhaled throughout the adventure come flying out, including Mario and Luigi. The now-conscious Peach, along with various toads, move to congratulate the Marios on a job well done. Bowser is angered to receive no credit for his part in the adventure, and begins raging at Mario. As they begin what promises to be another epic battle, the credits roll.

Afterwords, Bowser is seen lying in bed at his castle, nursing injuries apparently given to him by Mario and Luigi. Kurikkī, Heifā, and Patabon are there, apologizing for their treason and asking to rejoin the Koopa Troop. Before Bowser can answer, a messenger from Peach's Castle comes in, delivering a wrapped gift. Out pops Chippy, who flies off to help out with repairs. Seeing that the three former members of his army are still there, Bowser angrily asks why they aren't helping as well. The three are almost speechless, as this means they're back in the Koopa Troop. They run off, shouting their thanks back to their king. Looking inside Peach's present, Bowser finds it to be a cake with himself, Mario, Luigi, and Peach on it.

Overworld
While Mario and Luigi adventure through Bowser's Body, Bowser is walking around the overworld. Mario and Luigi can have influence on Bowser. They can pinch nerves to make Bowser panic. They can also touch Bowser's muscles to give him a power-up. Equally, Bowser can change the course of the Marios' adventure. For example, he can flood them by drinking from a fountain.

Overworld icons have slightly changed. They now display the health of the character. Bowser uses two buttons in the overworld, X to punch, and Y for firebreath. Mario uses A to jump, use his hammer or do a Spin Jump. Luigi uses B to jump, use the hammer or hiting Mario with his hammer, making Mario flat and little. While Bowser explores a 3-D overworld, Mario and Luigi explore a 2-D world inside Bowser's body, much like a traditional platformer.

Mario and Luigi Battle System
The battle system with Mario & Luigi is similar to the battles from previous titles. There are now six categories of attack during battle, as opposed to Mario & Luigi: Partners in Time ' s five, or Mario & Luigi: Superstar Saga ' s four. These are Jump, Hammer, Attack Parts (Bros. Items), Bros. Badges and Escape. The Bros can defend with their jump and their hammers. The Jump makes Mario and/or Luigi jump to dodge an attack or to counter-attack. The Hammer is used to counter-attack. The music played while battling is the same as the music played during the debut trailer, as seen in the Japanese site.

A new element has been added to battles, a gauge at the bottom of the screen with Mario and Luigi's heads on either end. When Mario or Luigi pulls off an action command, that brother's end of the bar fills slightly. When they meet in the middle, it's possible to use a Bros. Badge move. The effect varies with the equipped badge. The normal effect is to restore 20% of both brothers' HP. Badges can be bought in one of the shops in Toad Town. Some of the badges require that the action commands be pulled off perfectly (EXCELLENT is displayed), and some only need GOOD!. An extra block that appears in the battles can be used to swap the badges that brothers use.

Bowser's Battle System
Bowser has almost the same battle system as Mario and Luigi's, but with a few differences. He has different options: Punch replaces Jump, Fire Breath replaces Hammer and Enemy Attack replaces Attacks Parts. He doesn't have Bros. Badges. Instead, Bowser will get the vacuum ability only after the player advances further through the game. He can then swallow enemies to make Mario and Luigi fight them in his belly, or sometimes he can swallow parts of enemies that can restore his HP, raise defense or attack power, or rescue a Blocat. Bowser's defenses are the Punch and the Shell. Bowser's Punch can counter-attack an enemy. His spiky Shell can hit enemies that try to jump on his head.

Enemy Attacks are special attacks that use members of Bowser' army, which are Goombas, Koopas, Shy Guys, Bob-Ombs, or Magikoopas. These use the stylus. These characters need to be liberated to unlock these attacks.

Bowser will also have his very own battle system when he fights alone against equally-sized enemies. During these battles, the player holds the DS sideways like a book, and can perform moves with the touch screen and microphone. Sweeping the touch pen across the touch screen will make Bowser execute a Mega Punch against his enemy, while breathing into the microphone will make him breath fire. These battles are turn-based battles.

Playable

 * Mario
 * Luigi
 * Bowser

Friends

 * Princess Peach
 * Toadsworth
 * Toadbert
 * Yellow Star (Chippy)
 * Kamek
 * Toads
 * Brirock, a human like creature who seems to be made from ? Blocks.
 * Blodog, Brirock's pet.
 * Brirose, another humanoid creature made out of ? Blocks.
 * Blocats
 * Three assistants to Bowser:
 * Heifā, a green Shy Guy with a bag on his back, with a gray pipe and a Magikoopa's wand inside
 * Patabon, a red Paratroopa with a red bucket on its head, and green shoes.
 * Kurikkī, a Goomba that wears blue clothes and seems to look sad.
 * Hemoglobin, a species of block-like creatures inside Bowser that give hints and help with minigames.
 * Princess Mucus, who explains Bros. Badges.
 * Ibikki, the creator of Ibikki Tower and the Boo Light Machine.

Mushroom Kingdom

 * Torejan, a Treasure Chest with Banjo-Kazooie like eyes. It also has a dark version. It attacks by throwing items at the character. Bowser can counter the items back with his punch. He can also throw mushrooms at the character that can recover HP.
 * Magatsurī, a tree with eyes. They attack by throwing logs at the character. Some of them hold fruits that Bowser can inhale.
 * Kurishinbō, an obese red-brown Goomba with a lollipop. It is the first normal enemy Bowser fights in the game. It attacks by tackling the character. Bowser can inhale it's lollipop which will make the Kurishinbō run away crying.
 * Getagator, a dinosaur with Fawful's face. Bowser can suck out its teeth in battle. It can recover itself with beans and throw stuff to make himself attack in different ways.
 * Geranko, a Fawful-like ant with a drill for an abdomen.
 * Hanamūcho, Snifit flowers. As seeds they are Seed-Yan. They spit seeds at the character.
 * Gerawanwan, a parasitic green Sworm with Fawful's face possessing a Chain-Chomp. It can hide in the Chain-Chomp when it gets hurt.
 * Zuttsun (ヅッツン), A Thwomp with some kind of cold. If Bowser inhales his ice pack, Thwomp will take some damage after every move he does.
 * Jailrun, a living cage with a Bowser Minion inside. They contain either a Bob-omb or a Goomba. When one of the characters defeat the enemy, the trapped minion will throw a mushroom to the character as thanks.
 * Kikanbō, a train Goomba. Coal Ants can jump into it and make the Kikanbō attack more than usual.
 * Hagasanbon, a Pokey made entirely out of teeth. Bowser can punch it making all of the parts of the Pokey fly out of the field except for it's head.
 * Celebrity Lakitu, A Kingly Lakitu. This enemy rarely appears.
 * Gerapato, a UFO resembling Fawful that summons enemies. It is also seen in the story at points. Bowser can inhale it and let the brothers fight it.
 * Coal Ants, bugs made out of coal. They help out Kikanbō in battle.
 * Nooose, a round, tan, bird-like creature with mustache-like wings. There are two versions of this enemy. One with a green hat and one with a red hat. They can sing and recover one of their fallen allies. [[Image:Nooose.png|frame|right]]
 * Beehouse, a Walking Honeycomb/tree mix enemy that releases honey and bees. Bowser can inhale it's honey to recover HP.
 * Geppu WeedA purple bush-like creature with yellow flowers and red lips that shoots poison. Bowser can automatically kill this enemy in the overworld.
 * Gerahō, a Shy Guy with an orange robe and a Fawful mask. It also has a dark version. It can be killed by Bowser in one shot in the overworld.
 * Gerakamek, Fawful Magikoopas. They can summon shapes to crush the characters fighting it. Bowser can kill this enemy by just touching it.
 * A giant dark Bob-Omb that bears a similarity to the Shroob-omb from Mario & Luigi: Partners in Time and is filled with black stars. They are summoned at random points.
 * Gerasuhoppā, a grasshopper-like creature that resembles Fawful. Bowser can kill these in the overworld. They can jump attempting to crush the character. [[Image:Fawful Gasshopper.PNG|frame|right]]
 * Gerapū, a Monty Mole-like creature with a resemblance to Fawful. It also has a dark version. They attack by throwing boulders at the characters fighting it. If it has dirt on it's face, it will throw the boulder upwards instead of straight.
 * Metal Gerapū, a metal version of the Gerapū. It attacks the same way as it's nonmetal counterparts.
 * Uruhei, a clocked Bob-Omb. They can be stopped by a sleeping Gōnemu.
 * Doripen, some type of Bumpty with a drill instead of a beak. It tries stabbing the character with it's beak.
 * Gōnemu, a pig Golem that is found sleeping, and once awoke, they can spit brick blocks. They also shoot bubbles at the character while asleep.
 * Dark Gerahō, a dark purple Fly Guy with a blue Fawful mask. They carry giant dark Bob-ombs. Bowser can inhale them as well. If he doesn't, they will drop the bomb on Bowser.
 * Shokuchu, some type of bag-like enemies. If the Mario Bros. try jumping on them, they will be sucked into their hole on the top of their heads. They attack by tackling into the brothers.
 * Petarīno, they are similar to the boss Betarīno, but a lot smaller than Betarīno and are in groups.
 * Hermit Crab Drill, a Hermit Crab enemy. Like their name says, they have a drill-like shell that they can attack with. Mario and Luigi can't jump on it due to the shell.
 * Mekakobittsu, a Fawful-themed android. Once they are defeated, a little Fawful robot flies out of it. It usually flies away from battle.
 * Dark Mekakobittsu
 * Dark Mekakobittsu V2
 * Shadow enemies summoned by Dark Bowser. The enemies are Goomba, Koopa Shell, Thwomp, Spikeballs, Bullet Bill, and Bob-omb

Inside Bowser

 * Saibō, a new Goomba-like species that is clear with black eyes and houses an orange object inside itself (in Bowser's Stomach). It appears to be based off a cell. These are the first normal enemies that Mario and Luigi face. They attack by attempting to tackle into the brothers.
 * Katabō, a Goomba-like creature with a Buzzy Beetle-like shell. It is purple with black eyes and houses a yellow object inside. They also have black shells instead of blue and appear in Bowser's Stomach. It can't be killed with the Jump attack however can be by the hammer.
 * Togēba, Spinies with a normal spiky shell but goop-like body with blue-green color (in Bowser's Stomach). They can only be attacked by the Hammer move. Jumping on them will hurt the character due to it's sharp shell. [[Image:Togēba.PNG|frame|right]]
 * Thwomp-like bones (in Bowser's Stomach), it appears to be more of an obstacle rather than an enemy. There are three versions of this enemy.
 * Karakara Gessō, a wafer thin Blooper. It attacks by floating down from the sky trying to attack the character. When wet it becomes Mineral Gessō, a floating, stuffed, balloon-like Blooper.
 * Tampa-Kun (「タンパくん」), a round dumpy creature that looks like a Flurry and holds a club (in Bowser's Stomach). It grows whenever Mario and Luigi attack it. It also makes shockwaves with it's club.
 * Jūshī, a living piece of meat (in Bowser's Stomach). It tries to roll into the character.
 * Karorin, a Flame Monster holding two small logs. It can eat Jūshī and turn them into Karorin. They try rolling and hitting the brothers with their flames.
 * Shinapun, a red and yellow spherical creature. It throws red and green energy balls at the characters. It can also split into two enemies that are generally weaker.
 * Dokkun Flower, a Piranha Plant that resembles a vein (in Bowser's Stomach). They spit poison at Mario and Luigi.
 * Energy, a ball of energy that can switch between POW, DEF, and SPEED forms. POW form Energies try to punch the brothers, DEF forms can jump into a character to give it more defense and SPEED forms can attempt to tackle into the brother a couple of times.
 * Porippū, a blue palette swap of Tampa-Kun.
 * Air Puku, a fish that has been influenced by the Dark Star.
 * Nioinī, a cloud that has been influenced by the Dark Star.
 * Air Pun, a palette swap of Shinapun. It attacks the same way as it's counterpart.
 * Air Gun, a cannon manned by an egg shaped creature. Once the cannon gets destroyed, the egg character will run away.

Bosses

 * Dark Fawful
 * Brirock, a block-like character. He fights Bowser, showing him how to use the Vacuum command.
 * Blodog, Brirock's guard dog. He fights Bowser thinking he's an intruder.
 * Bowser, the first boss in the game. He is fought by just Mario. The bros. fight him again later in the game.
 * Betarīno, a Bug-like creature that doesn't allow Bowser to breath fire
 * Bowser's Castle. Giant Bowser fights it.
 * Metaboss (two times)
 * Gera Express, a giant train with Fawful's face. Giant Bowser battles it.
 * Marine Pipe's Statue
 * Blooper's Statue
 * Imounu (a Birdo-Wiggler Mix)
 * Bifīzu Person, three creatures that assist Imōnu.
 * Straw, a heart-shaped device that Imōnu uses to steal Bowser's HP.
 * Wiggler
 * Leaf Heihō, a Fly Guy with a seed for a propeller.
 * Arukaroten & Betakaroten, who kidnap Peach.
 * Sage Imounu
 * Ibikki Tower - A clockwork tower that resembles Ibikki. Bowser must become a giant to fight it.
 * Bowser's Memory ML
 * Chakuran - the guardian of the third Star Vaccine
 * Garbage Monster - A monster made from a trashcan.
 * Garbage Henchman
 * Blizzard Metaboss - Metaboss powered up by Fawful.
 * Snowbittsu - A snowman assistant to Metaboss
 * Dark Star
 * Dark Satellite
 * Super Peach Castle, a piece of Princess Peach's castle that Fawful made animate. Giant Bowser fights it.
 * Dark Bowser and the Dark Fawful Bug.
 * Shroob Seijin (optional)

X Bosses
The game also contains a Battle Colosseum that gives you an option to fight 7 optional bosses. They're tougher versions of bosses that Mario and Luigi already fought. This mode also requires brothers to finish the enemy in less than set number of turns. These bosses are:


 * Imōnu X
 * Arukaroten X
 * Sage Imounu X
 * Magical Rod
 * Bowser's Memory ML　X
 * Garakuta Monster X
 * Garakuta Kobun X
 * Dark Star X
 * Dark Satellite X
 * All other bosses from Challenge Hall in a row + Bowser X

Locations

 * Bowser's Body
 * Junk Space
 * Surprise Bone
 * Toad Plaza
 * Challenge Hall
 * Power Space Arm
 * Pump Space
 * Fire Pipe
 * Power Space Stomach
 * Sensitive Spot
 * Power Space Bottom
 * Metaboru Space
 * Power Space Leg
 * Power Space Nose
 * Energy Space
 * Press Tower
 * Memory Warehouse
 * Lower Back's Tsubo
 * Power Space Chest
 * Air Space
 * Pipe Plaza
 * Mushroom Kingdom
 * Bowser's Castle
 * Ekubon's Forest
 * Gepū Cape
 * Ibikki Tower
 * Musshība Beach
 * Otapuku Meadows
 * Peach's Castle
 * Railroad
 * Road to Bowser's Castle
 * Toad Town
 * Underground Tunnel
 * Zutsūda Lake

Differences
Mario & Luigi RPG 3 has some difference with the first two Mario & Luigi games.

Gameplay Differences

 * This is the first Mario & Luigi game to have optional bosses.
 * Unlike Mario & Luigi: Partners in Time for the Nintendo DS, this game makes greater use of the DS's touch controls and microphone.
 * This is the first game in the Mario & Luigi series to have a playable character that is not Mario, Luigi, (or their baby forms), other than Toad very briefly during the opening.
 * The player can equip Mario & Luigi with pants, gloves, shoes, socks, and accessories instead of just pants as in the first two Mario & Luigi games.
 * Badges have a different function. Bro. Badge moves can be preformed with them. This game contains 8 badges, which is notably less then the previous Mario & Luigi games.
 * M Blocks and L Blocks are gone.
 * This is the first Mario and Luigi game that has no Rex.

Other Differences

 * This is the first Mario & Luigi game that does not have a main female antagonist.
 * This is the first Mario & Luigi game that a normal Yoshi does not appear in. Also, Professor E. Gadd did not make a apearance.
 * Mario & Luigi do not have a suitcase, unlike the first two Mario & Luigi games.
 * Unlike the first two Mario & Luigi games, Mario & Luigi 3 does not have the same ending music the first two games.
 * Unlike the first two Mario & Luigi games, this is the first to have a save block instead of a save book.
 * The save-screen or load-file-screen no longer resembles a notebook.

Release Differences

 * This is the first Mario & Luigi game to be released in Japan before any other country.

Solo Pictures
NOTE: Solo artwork for this game which is not shown here was previously used in Mario & Luigi: Partners in Time.

Trivia

 * Mario & Luigi RPG 3 is the first game where Princess Peach has the power to levitate other people. Apparently, this is because she must pray in conjunction with Yellow Star's powers to do so.
 * This is the first time in the Role Playing Games that a sequel has been released on the same system as its predecessor.

Other Links

 * Japanese Site of Mario & Luigi RPG 3!!!