Mario & Luigi: Paper Jam, known in Europe and Australia as Mario & Luigi: Paper Jam Bros. And in Japan as Mario & Luigi RPG Paper Mario Mix, is an upcoming role-playing video game developed by AlphaDream and published by Nintendo. The game is the fifth title in the Mario & Luigi series, crossing over with elements and style of characters from the Paper Mario series. It is scheduled for release on the Nintendo 3DS in December 2015, and in North America on January 22, 2016.
One day, Luigi accidentally trips and knocks over a mysterious book containing the Paper Mario world, causing the paper-thin residents within it to spread across the Mushroom Kingdom. Afterwards, Bowser combines his evil army with those of his paper-thin counterpart, Paper Bowser and they kidnap Princess Peach and her counterpart, Paper Peach. Mario and Luigi must now team up with Mario’s counterpart, Paper Mario, to set everything right, defeat Bowser and Paper Bowser and bring all the paper people back to the book.
The story of Mario & Luigi: Paper Jam crosses together the universes of the Mario & Luigi and Paper Mario series, resulting in the sprite-based residents of one universe meeting their paper thin counterparts from the other. As such, players control a team consisting of Mario, Luigi and Paper Mario, whose actions are controlled by pressing A, B and Y respectively. In addition to the moves Mario and Luigi can make in their series, Paper Mario can use his paper thin body to perform his own unique actions, such as squeezing through tight gaps or turning into a paper airplane in battle to help the bros. Like previous games, battles incorporate various mechanics such as timing attacks or using special abilities. During battle, Paper Mario can make copies of himself, allowing him to deal extra damage or attack multiple enemies at once, as well as use special techniques where all three fighters attack together. There are also sections where players control a giant Papercraft Mario and fights other papercraft enemies.
Source – Wikipedia