Sync likes to hide secrets on his maps, has anyone found anything on elder yet?:)
(I wouldn't count the audio file, that just gets played when you fall into lava)
The map looks like a compilation of ideas from other maps. I.e. near GL it's like in Repent. Maybe Sync also compiled in one of his secrets, like hitting a button outside the map with a grenade.
Program Files (x86) -> Steam -> steamapps -> common -> Quake Live -> baseq3 -> Elder ->textures -> se_gothic -> runes.jpg and runes_motion.jpg
Since those 2 are not used anywhere in the map normally, the easter egg is probably runes dropping like confetti or some swirl storm is the intended effect. Have not figured out how to trigger it though.
May I also suggest you make a high quality config and set everything to the default to see the map as sync intended, it's a beautiful map, real eyecandy ))