RaTEoREkiSImeAra

raTEoREkiSImeAra (called on the JASRAC database) is Disc 3, Track 13 on the XenobladeX Original Soundtrack. It is split into two parts: the first plays from the start until 3:55, and the second plays from then until the end.

The first part plays as the battle music for the in, as well as the cutscenes immediately before and between the two phases of the boss. It also plays as the battle music for the during the Dark Matter Phantom Time Attack Mission.

The second part plays as the battle music for Telethia, the Endbringer and Telethia Plume. It also plays when Telethia swoops down and easily does away with the Tainted Sphinx in, as well as when it approaches the party during The Nopon Heir.

Etymology
Separating out the lowercase letters from the uppercase in the title gives 'raokimera' and 'TERESIA'. These are alternate romanisations for 'Lao chimera' and 'Telethia'. The latter refers to Telethia, the Endbringer; the former likely refers to Lao's transformation as a chimera, although it is unclear what this track has to do with that.

The JASRAC version of the title is, uncharacteristically, simply a different permutation of the original. It is unknown why this title was still kept 'encoded' in this way when many others were not.