life bar or missing too much the player is taken to the Results Screen which rates the player's performance with a letter grade and a numerical score among other statistics. After completing a song the player may be given a chance to play again depending on the settings of the particular machine. The number of songs in credit is 3 songs + bonus on all versions other than Extra Mix and NX2. Extra allows changing the game to 2+1 while NX2 is 2+1 by default on Arcade Station (3 songs in all other Stations). If the player gets an A ranking or better on all songs in a game, the player earns a "bonus stage". Later games display how many A or S grades a player has gained that game on the select screen via a life bar featuring hearts. Getting any score other than an A ranking or higher will lower the number of hearts. If the player passes a song with a D rank or lower but does not fail then the player's song set will be reduced to just two songs. Difficulty The steps for the various levels of difficulty available for a particular song are ranked using a scale, the format of which varies from version to version. Early games had difficulty ranked by "Station" with all songs on a station having the same difficulty. Stations became ways to select song types in Pump it Up Zero and then became ways to select different game modes after the New Xenesis series. Some stations are meant for more advanced players despite hosting a selection of difficulties inside of them. For example, the Music Train, World Max and Mission stations are often for advanced players while Arcade or the Easy station are for general players. Before Exceed was released, the difficulty for all game modes ranged from 1 to 10, with the exception of "Vook", a song introduced on The Premiere 2, which was level 12 on Double mode. Level 1 was the easiest song available at that difficulty while level 10 was reserved for the most difficult. With Exceed's debut all levels were reworked into a unified range from 1 to 10 for most modes, up to level 15 for Crazy mode and ranging as high as 20 for Nightmare mode. Successive games have resulted in higher level ranges for all song difficulties as well as an