Level up

Level Up is a term often referred to in RPG games. A character must defeat enough enemies in battle to gain enough experience points to level up. As the character grows to higher levels, more experience points are needed to level up. Once the character levels up, their stats are increased and he may also learn a new special skill or attack.

Paper Mario and Paper Mario: The Thousand-Year Door
In both of these games, Mario must choose one of his stats to boost. If he chooses HP or FP, his maximum for that stat will go up by five points. If he chooses BP, his maximum BP will go up by three points. The two other stats remain unchanged.

Mario & Luigi: Superstar Saga and Mario & Luigi: Partners in Time
In these games, HP, Bros. Points(Superstar Saga only), Power, Defense, Speed, and Stache are all initially increased from zero to five points immediately after leveling up. Mario and Luigi can then choose any stat they want and give additional points to it. A roulette determines how many additional points are added: up to five in Superstar Saga, and up to six in Partners in Time.