Here is the hands down easiest way to spot these differences. Cross your eyes until the images make a central image. The differences will kind of flash. might take a little bit of practice, but seriously it makes this pretty simple.
Great writing. Better writing than most big budget games I play. You should seriously consider doing an RPG or something that is more heavily writing driven. 5/5
 "WarLight"){kind=icon}
 "Moonlight Differences"){kind=icon}
 "Grey"){kind=icon}
 "Viricide"){kind=icon}