Dark Note Dark Notes are a feature in " Theatrhythm Final Fantasy " , accessed in the Chaos Shrine gameplay mode . They consist of a paired Field Music Sequence and Battle Music Sequence , generated at random with the creation of the Dark Note . The player ' s first Dark Note will be generated at some point during normal gameplay , unlocking the Chaos Shrine in the process . Thereafter , new Dark Notes are generated by clearing the player ' s newest Dark Note . Structure . The relevance of the classification ( e . g . Round , Etude , etc . ) and name of the Dark Note is unclear ; however , the other two properties attributed to Dark notes are meaningful . The Number ( " No . " ) , which is the average level of the party that created the Dark Note , determines its difficulty . Higher numbered Dark Notes have the triggers moving faster , and extremely high numbered Dark Notes even introduce rotating slide triggers . The Movement ( " Mv . " ) is a two digit number that determines the two tracks that make up the Dark Note . The construction of the scores is only partly random ; each track is split into four segments , each of which is taken from one of four scores for that track : red , green , blue or yellow . Thus , there are a finite number of permutations – 4 = 256 per track , and thus ( 256×10 ) = 6 , 553 , 600 unique Dark Notes . The increased difficulty at higher numbered Dark Notes , therefore , comes not from more complicated scores , but from increased trigger scrolling speed , as well as the addition of rotating slide triggers at Nos . 90 to 99 . Note also that while the Feature Zone and Feature Drive can begin or end at a segment split , they will never have a split within their duration , though it is possible for the boundary between them to be on a split . In the BMS , the enemies faced by the player follow a simple loop of two fixed enemies , then one enemy that will differ depending on which Boss the player will be facing , then a boss enemy . After the boss , it repeats from the two fixed enemies . The bosses faced depend on the player ' s performance . Firstly , in the FMS , there is a sign which , if the player reaches it in the course of the FMS ( by hitting triggers well and having high agility ) , they can encounter Boss Nos . 2 and 3 in the BMS ; otherwise , they can encounter only Boss No . 1 . Should the player do well enough to obtain the ability to fight Boss Nos . 2 or 3 , which boss is fought is determined by their party members ' remaining amount of hit points . If the party ' s health is high ( more than about / of their maximum total ) , then the player will fight Boss No . 3 . If the player ' s health is lower than this , the player will fight Boss No . 2 instead . The player may fight more than one boss in the course of the BMS , depending on how many enemies they defeat , and the criteria are stipulated again with any fights beyond the first . For example , should a character use a curative ability to push the group after fighting Boss No . 2 , the player may find himself fighting Boss No . 3 in the next round . Likewise , should the player lose a significant amount of HP after fighting Boss No . 3 , they will fight Boss No . 2 instead . Bosses appear as every fourth enemy in the BMS , and should the player manage to qualify to fight Boss No . 3 , its arrival is heralded when the battle begins against the enemy preceding them . Chaos can appear as Boss No . 3 in Dark Notes numbered 90 or above . His presence can be identified if Libra reveals any of his drop items when the Dark Note is generated , or otherwise , if upon reaching the BMS , it is seen to have the Chaos Shrine as a backdrop instead of its usual background . Rewards . Aside from occasional Rhythmia rewards , Dark Notes are the main source of shards that contribute towards unlocking characters . Notably , Navy ( Kain ) and Black ( Sephiroth ) shards can " only " be obtained from Dark Notes . Each Dark Note has three bosses in the BMS section , which each have three possible drop items . Boss No . 1 has one shard among its drops , Boss No . 2 has two , and Boss 3 has 3 possible shards , though not all drops are shards . Each shard color can only be obtained from boss enemies in certain Dark Note number ranges .