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• All of Naplock's attacks can be dodged or countered by jumping, with its snot bubble attack also missing Mario & Luigi entirely even if nothing is done.
• Dark Mechawful's punch attack can be countered with Mario & Luigi's hammers, while its countdown attack is replaced by the same star attack used by the Dark Mechawful head, which can fight Mario & Luigi in normal gameplay if Bowser inhales it. However, in a hacked Dark Mechawful fight, this attack progresses extremely slowly.
• The smoke signals at the start of Choomba's charge attack are changed from fist and shell icons to "M" and "L" ones, indicating which brothers it will charge at and in which order; the attack can also be countered by hammering.
• Dark Trashure's thrown items can be avoided or countered by jumping, similarly to its standard counterpart. However, the items move far faster than those thrown by a regular Trashure or a Dark Trashure fought by Bowser.
While most of these behaviors appear to be failsafes, Choomba is unique in that the "M" and "L" smoke signals are not present anywhere else in the game, indicating that at one point in development, Mario & Luigi would've been able to explore the Tunnel, where Choombas are fought.
Meanwhile, when hacking the game to allow Bowser to fight enemies that can only be encountered by Mario & Luigi, most of them will either crash the game, flee immediately, or display glitchy behavior. One unique case is Magifoofas, which can be inhaled by Bowser (despite the Vacuum Block not indicating this), indicating that the developers considered letting him encounter them in some form.
The Cutting Room Floor article:
https://tcrf.net/Mario_%26_Luigi:_Bowser%27s_Inside_Story#Unused_Enemy_Behaviors
YouTube video showcasing the unused enemy behaviors:
https://www.youtube.com/watch?v=b3DTjRZvhOM
https://tcrf.net/Mario_%26_Luigi:_Bowser%27s_Inside_Story#Unused_Enemy_Behaviors
YouTube video showcasing the unused enemy behaviors:
https://www.youtube.com/watch?v=b3DTjRZvhOM
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In Mario & Luigi: Bowser's Inside Story, there are quite a few unused rooms without anything in them, most of them used for testing. One of the rooms appears to be a pipe in Dimble Woods leading into bowser's body that can only be accessed through the use of hacking. It was probably removed because once you've found all the attack pieces there you had no need to go back. Another one of those rooms are in Dimble Woods, along with what appears to be the Tower Of Yikk on the ground. This might suggest that originally bowser was supposed to fight it in dimble woods, but it was replaced with Bowser's Castle.
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Upon meeting Broque Monsieur as Mario and Luigi at his shop in Dimble Wood, he says that he has met them somewhere before but can't remember. This is probably a reference to when Bowser first got the Vacuum Block and Broque saw Mario and Luigi inside of Bowser.
Monsieur does not like that the brothers hit the ? blocks around the kingdom and decrease their "value" and refuses to sell them anything.
Monsieur does not like that the brothers hit the ? blocks around the kingdom and decrease their "value" and refuses to sell them anything.
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After the battle, Starlow finds out that these creatures once invaded the Mushroom Kingdom, and that Mario and Luigi Spoiler: defeated them as babies. Starlow also finds out that Spoiler: Luigi defeated the Shroobs by crying in the past, another nod to Partners in Time . This almost assures that the Mario and Luigi in Bowser's Inside Story are Spoiler: the babies in the previous game.
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