- Level Easy, Hard and Chaos: At Xenon's song selection screen, press the dark circular sign that says 'Deemos'.
- This song is a hidden song.
- This song can also be found in Deemo.
- Sairai (再来) is Japanese for "Return" or "Second Coming".
- This is one of the two songs in Cytus II to have a BPM less than 100, the other one is Celestial Sounds (KIVΛ Remix).
- Its time signature is 3/4 and changes to 4/4 towards the end.
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