When trouble happens in the stars. It's up to Mario and Luigi to set things right. With some new friends, this journey will be beyond the stars. In honor of the first 3 Paper Mario games.

Mario and Sonic's worlds are in chaos. A mysterious new foe and an organization group have used their powers to collide their universes into one and slowly starts to collapse. Mario and Sonic and co must team up and work together and stop this new threat and say their universes or else everything will be turned to nothing.

"Light and Dark are like two halves of the same coin. One can't exist without the other." Mario suddenly woke up from what he assumes as a nightmare. But in reality he learns that his 'dream' and the negativity that has spread through out the Mushroom Kingdom share a connection. Not only that...Luigi seems to have the same connection, but to light and positivity instead. Could this only be a coincidence? The two don't think the same at all. They both eventually find out that Luigi has the power over Light...and Mario has the power over Darkness. While Mario struggles to control this darkness they find that the balance between those two entities have become disconnected. Will light prevail and darkness expire? Will darkness prevail and light expire? Or shall the connection become whole once more, and make the world balanced again? Find the answers to these questions by reading this yourself.