No3=NO.EX01

no3=NO.EX01 (called in the JASRAC database) is Disc 1, Track 3 on the XenobladeX Original Soundtrack (making it the third track in 0rCH-SUITE "X"). It is a boss battle track, playing in the following battles, as well as the cutscenes immediately prior:
 * Almandal in Chapter 7.
 * Ryyz and Dagahn in Chapter 8.
 * The Vasara and Deva Caladar in Chapter 9.
 * The Zu Pharg in Chapter 10 (during the 2nd phase of the battle).
 * The Demise Ictus during Then and Now.
 * The first set of Nameless Caladars during Lionhearted.
 * The Marnuck Commander and Marnuck Soldiers during Reporting for Duty (including the prior cutscene when Nagi goes ham on Orton's captors).
 * The Grudge Tersqual during To Serve Nopon.
 * The Twin Qmoeva during Rites of Ruin.
 * The Soghu Caladar during Leaving the Nest.
 * Blood Despair during Rise of the Blood Lobster.
 * Ozuchi Caladar during The Gauntlet.

Etymology
The no3= at the start of the track indicates that this is the 3rd track on 0rCH-SUITE "X". The significance of 'NO.EX01' is unknown.