individual songs, but are also given a Challenge Score. Each song is assigned a point value on a scale from 1 to 50 (formerly 1 to 43) regarding to the difficulty, and at the end of a game in one of these modes, the total is tallied. Additionally in these modes, options called "Norma" and "Ojama" may be used to add point values to the player's Challenge Score. A "Norma" is a set goal, while an "Ojama" is an active means of periodically distracting or disrupting the player. Up to two options can be activated at once. On specific numbers, a player may be allowed an "EXtra Stage", an additional stage in which the most difficult charts (EXTRA or "EX" charts) for certain songs may be played and unlocked. EXtra stages use a different gauge than usual, a "Stamina" gauge similar to the life bar in a fighting game, or Dance Dance Revolution's Life Gauge, where complete depletion means the end of the song. It was renamed "Normal Mode" in Pop'n Music 20 Fantasia. Cho-Challenge Mode (超CHALLENGE モード, "Super Challenge Mode") is similar to Challenge Mode, except that another accuracy score is added, "Cool". This makes songs played in these modes significantly more difficult to achieve high scores on, as the value of "Great" and "Good" are decreased. Starting from pop'n music portable on console releases and Pop'n Music 20 fantasia on arcade releases, "Cool" is always on, regarding to Challenge Mode and Cho-Challenge Mode are combined into one single mode. Osusume (オススメ, Lit. "Recommendation") Introduced in Pop'n Music 9 is Osusume (オススメ, Lit. "Recommendation") Mode, where the player is asked a series of questions, and the game provides an Expert course based on the player's answers. It was removed after Pop'n Music 11. Osusume was reintroduced in Pop'n Music 20: Fantasia as a song category within normal mode, containing a selection of songs the player might like, based on the player's song selection history. Net Taisen Mode (NET対戦 モード, "Net Battle Mode") With the introduction of the e-AMUSEMENT system in Japan, pop'n music 12 Iroha is the first game to feature "Net Taisen Mode" (NET対戦 モード, "Net Battle Mode"). This mode allows players to compete over the e-AMUSEMENT network in real time with players on other e-AMUSEMENT-ready cabinets. In Pop'n Music 17 The Movie, a CPU-emulated version of this mode has been added, similar to the "Taisen" mode found