Mario and Luigi: The Legend of the Neonlight Stars is the 5th installment to the Mario and Luigi series. You get to play as a lot of characters now, like in Bowser's Inside Story how you got to play as Mario, Luigi and Bowser. This game involves the Wii U Gamepad for special battles with some of the characters, since the game will be Wii U exclusive.
All of the characters in the game have their own buttons, yet some will share the same button. Mario, Luigi, Peach and Bowser are all playable as for they become a team and are the main protagonists of the game. Mario uses the A button, Luigi uses the B button, Peach uses the Y button and Bowser uses the X button. Wario and Waluigi are also playable and sometimes the story will switch to them. They also end up teaming up with Boshi, Yoshi's rival for fastest dinosaur. Wario use A, Waluigi uses B, and Boshi uses X. Yoshi is also playable, and he'll use A, too. Then we have some new characters. Black Belt Koopa, who uses A, Masked Hammer Bro, who use B, and Caped Shy Guy, who uses X. Then at a certain point in the story, all of these characters team up to save the doomed world.
Chapter 1: The Quest Begins
Mario and Luigi get an invite to Peach's Castle. Peach wants to give them a super buffet for all the times they've risked their lives for saving her. Mario and Luigi hurry to the castle. As soon as they get there and arrive at Peach's Castle, Mario and Luigi see Starlo, Twink, and Stuffwell from their previous adventures. As Mario and Luigi get ready to eat their buffet, Bowser storms in the castle and attempts to kidnap the princess. But Mario and Luigi try to stop Bowser. Starlo, Twink, and Stuffwell come in at random times and explain how to fight again, like in every game they do. After the 2 bros defeat Bowser, Bowser soon regains strength and gets back up. He sees the buffet and helps himself. Mario and Luigi get upset that Bowser starts eating their buffet. Peach then firmly explains how that buffet is for Mario and Luigi for all of the times they saved her from him, and so he was basically eating their work. Bowser says how he doesn't care and he keeps eating. Peach sighs and just says that they should just go out to the balcony. And when they do, they see that all of the Mushroom Kingdom is covered in darkness.