Paper Mario is probably best described as an RPG platformer. Mario travels through various lands, from desert to rainforest, on land, water and air, platformer style, jumping on objects, breaking blocks, and uncovering hidden items. But he interacts with characters, enemies, and storyline development RPG style. The game begins as Mario sets out to save the Princess from the evil Bowser, who has stolen a magical artifact called the Star Rod and made himself invincible. Jealous of Mario's popularity and wanting desperately to be favored by the Princess, Bowser has kidnapped her against her will and taken her to his floating castle high in the skies above the land. Mario quickly finds that the only way he can beat Bowser and rescue his main girl is to retrieve seven Star Spirits, magical entities that grant wishes, and use them against his evil foe.