* FanNickname: While ''[=RayCrisis=]'' is the only game in the series that wasn't officially named "''Layer Section''" in Japan, fans sometimes refer it as ''Layer Section III''.
* NoExportForYou: The PC ports of ''[=RayStorm=]'' and ''[=RayCrisis=]'' were released in Japan and Europe, but never to North America. Suffice to say they can run on Windows computers without having to change the regional Unicode settings of your PC, thus making them import-friendly... [[KeepCirculatingTheTapes if you can find copies of these games in these times]] (especially ''[=RayCrisis=]'').
** The ''Simple 1500 Series Vol. 75: The Double Shooting: [=RayStorm=] × [=RayCrisis=]'' compilation was only released in Japan. The [=PlayStation=] Network re-release of these games also stayed there.
** The [=PlayStation=] 3 version of ''[=RayStorm=] HD'' was released only in Japan.
* WhatCouldHaveBeen: ''[=R-GEAR=]'', a true sequel to ''[=RayForce=]'' was originally planned until the development of ''[=RayStorm=]'' took its place.