Mario
Our Hero (as always). Mario uses the power of one of the Lumas to save Princess Peach and the galaxy. He has blue overalls, a red shirt and brown boots.
Luigi
Mario's brother who is rescued several times.
Bowser
The villain (again as always). He is a big reptile-like creature that kidnaps Princess Peach and tries to create his own galaxy to take over all the others.
Princess Peach
Bowser's prisoner (once again, as always). She has a pink dress and long blond hair. She is the princess of the mushroom kingdom.
Rosalina
This Keeper of the Comet Observatory floats through the cosmos with curious star creatures, called Lumas. Her past is shrouded in mystery.
Polari
This elderly Luma is Rosalina's most trusted advisor. He knows all about the observatory, and if you speak to him, he will show you a map.