"Paper Mario" combines traditional role-playing game (RPG) elements with concepts and features from the "Mario" series. For the majority of the game, the player controls Mario, who can jump and use his hammer to overcome physical obstacles placed in the game's overworld. Many of the game's puzzles and boundaries are based upon the abilities of Mario's partners, who each have a specialized skill required for progression in the game. The player accumulates partners as they advance into different locations; only one partner can accompany Mario in the overworld, although the player can interchange them at any time.