List of Mario & Luigi: Bowser's Inside Story glitches
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This is a list of glitches in the game Mario & Luigi: Bowser's Inside Story. For a list of glitches related to the remake, Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey, see List of Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey glitches.
Glitches
NOTE: Unless otherwise noted, all names are conjectural.
Bowser Punch Glitch
The player must be Mario and Luigi inside of Bowser's Body. After saving, quitting, and re-opening the game, the player must press 
. Instead of breathing fire, Bowser will do a punch.
Frozen Battle
If the player is battling Bowser X, and when he is doing the attack where he grows giant, and one of the bros is hit by the fire, then they will fall behind, and sometimes the game will freeze. The music is still playing, although it is playing the same note over and over again.
Luigi Wearing Mario's Clothes
When the player goes to the blue area of the Flab Zone and jumps into the mucus and through the pipe, Luigi will oddly fall in front of Mario. Luigi will then have half green and half red sleeves and Mario's overalls. When the player jumps as Luigi, he will jump "out" of Mario. When Luigi falls back down, he will look like he fell back "into" Mario.
Save Block Lag Glitch
Bowser should be facing a save block, close enough to punch it. The player must save while inside Bowser's body. They must then quit the save file. After reloading the game, the player must press 
or to make Bowser punch. He will do the slide punch animation, and after a few seconds, will hit the save block.
Stuck Statue
When Bowser is pushing a Statue of Fawful in Bowser's Castle, there is a glitch where Bowser will get the statue right to the wall but will be stuck. Mario and Luigi can't do the double jumps on Bowser's legs to make him push, they will only do normal jumps. Bowser's minions won't push the Statue either though, making the Statue stuck. If the player restarts the game then the glitch will be fixed and the game will go on as normal.
Confused Action Icons
When the player begins the Mushroom Ball challenge in Toad Town and has the ability to tunnel underground, sometimes popping back out will cause the action icons to be in a glitched state after getting the Mushroom Ball out of the ground. This will move the action icons further up and make the game think they have or have not been switched and also frozen in place.
The action icons will also disappear if the player opens and closes the star menu, though they still function correctly. The player can fix this by simply entering any area.[1]
Talkative Pep
When the player defeats a Pep that's in its POW form and tries to attack, a glitch may occur. Mario or Luigi must counterattack by using their hammers right when the Pep makes a sound effect, and if they defeat the Pep, during the rest of the battle, and even in the victory scene, the player can hear a Pep sound playing over and over again.
Trapped in the Pipe Yard
Warning! Performing this action may corrupt your game's save file.
If Bowser is bloated after eating one of the leftovers, once the Flab Zone is active, the player must go to the Pipe Yard, and when they do, a glitch may occur. Mario and Luigi will keep walking, but Luigi will be stuck. The player has to reset the game after this. However, if the player (as Bowser) saves anyway after the glitch is performed, the save file will become bricked, making the Bros. unable to progress through the Pipe Yard.
