Canon futuristic AU - my theory.
I've pretty much said it before, but I believe this AU is a future where war broke out across Runeterra, possibly after the Void attacks. I'll state what I think the skin lines represent and their place in the AU. So FAR, I kind've have a theory that this may occur if Ryze is able to hide all the World Runes, thus no way to wage war other than cybernetic augmentation and evolving warfare.
Mecha: Piltover-originating robotics designed from various figures. Mecha Sion being the one rogue unit. Program: Possibly the sister-faction to the Mecha line.
PROJECT: Ionia-originating group based on augmentation. Katarina and Zed are possibly two rogue or freelance units.
Battlecast: Zaun's faction originating from Viktor bringing his plot to life. They're based on dehumanization, and removing weakness. They, and the Mecha team have proven to be capable of convincing voidborn to join their movements.
Eternum: Odd? Probably. Most of the super-energy voidborn create, (ex: kha'zix's evolved R form.) The Eternum skins could possibly represent augmented Voidborn and possibly demonic forces, to deal with the mortal races.
Resistance: Possibly a small guerilla force dedicated to fight Viktor's battlecast. Full Metal: Nemesis organization to the Battlecast possibly. Could be a seperate version of Viktor's movement, except more on the good side.
Steel Legion: Demacia's augmented force. Nothing special aside from special tech designed to fight the enemies of the future. Unnamed bio-related skin line(theory)/Augmented Singed & Bioforge Darius: Noxus & Zaun's answer to the Steel Legion. This could also be the same for the Crimson Elite skins.
Special Forces: Unknown origin, though it could be a military force related to future Bilgewater or elsewhere. Though I believe it COULD have a place.
Omega Squad + the military organization behind it: Definitely a possibility for the future Yordle race. The gear Teemo has could have been made to "hunt big game," meaning the voidborn possibly running around the jungles and land. Though this could be BEFORE battlecast, PROJECT, and Mecha factions become prominent.
This is just my best guess so far, I don't know.
