Who could be the main antagonist in a Mario and Luigi crossover fanfiction?

Bowser could be the main antagonist. He might see Luigi's transformation as an opportunity to mess with Mario and the Mushroom Kingdom. He could try to use Luigi's new form to his advantage, perhaps by trying to make Luigi a spy or by using his new identity to cause chaos among the kingdom's residents.

Maybe a new character could be the main antagonist. A powerful and mysterious being that Luigi stumbles upon during his escape. This character might have some vendetta against the Mario brothers or just be generally evil and wants to stop Luigi's journey for its own malicious reasons.

Well, the main characters are obviously Mario and Luigi. They are the ones who usually drive the story forward in this kind of fanfiction. Sometimes, Princess Peach might also be involved. For example, she could be the one who asks Mario and Luigi to find some special lemons for a grand banquet she's planning. Yoshi could also make an appearance, maybe he has a taste for lemons too and joins Mario and Luigi on their lemon - related adventures.

Another possibility is that a group of Koopa minions could be the main antagonists. They might be under the orders of Bowser, but they have their own little schemes going on. They could target Mario - turned - girl because they think she'll be an easier target in her new form, but they are in for a big surprise when she shows her strength.

In the Mario and Luigi life story, the two central characters are, of course, Mario and Luigi. Mario is known for his red cap and blue overalls. He is the one who usually takes the lead in their quests. Luigi, his younger brother, has a green cap and overalls. He may be a bit more hesitant at times but is a great help to Mario, especially when they need to work together to solve puzzles or defeat enemies.

The two main characters in 'Mario and Luigi: The Inside Story' are Mario and Luigi. Mario is the more well - known and heroic of the two, often taking the lead in their adventures. Luigi, his brother, is also very important. He has his own unique abilities that complement Mario's, and together they form a great team to face the challenges in the game.

One idea could be that Mario and Luigi get transported to a strange new world where the rules of their own world are all mixed up. They have to use their combined skills in a whole new way to find their way back home. For example, Luigi might have to be more brave and take the lead in some situations while Mario has to use his speed in different ways than he's used to.

A possible main antagonist could be Aizen from 'Bleach' who somehow gains the ability to control the powers from Lucy's world as well. He could use this newfound power to try and take over both the Bleach universe and Lucy's world. His cunning and powerful abilities would make him a formidable foe for Lucy and the Bleach characters to face.

Maybe Salem could be the main antagonist. She has been a long - standing evil force in the RWBY world. If Superman shows up, she would likely view him as an obstacle to her ultimate goal of destroying the world and remaking it in her image. She could use her Grimm army and her own dark magic to fight against Superman and the RWBY characters.

It could be a powerful Sekirei who sees Shirou as a threat to the Sekirei Plan. This Sekirei might be very traditional in their views and not like the idea of an outsider like Shirou interfering.