We know that Aurelion Sol refers to alien threats in one of his voicelines which I don't think are void creatures. "The depths of space crawl with terrible entities. Pray they ignore this world." Also with the retcon of Darkin no longer being alien invaders I thought having more champs that come from other worlds might be fun. Also if you think it's impossible then remember that Aurelion Sol is technically an alien.
I don't want that to happens to be honest. We already have Shurima plot, Freljord Plot, Shadow Isles plot etc. you get me, then this is only the 1/6 of the Runeterra. I hope they remain within the world itself
Riot had previously stated that they aren't going to be exploring other worlds.
The closest we may get are celestial beings similar to 
or 
. They aren't aliens from another world, rather something closer to spirits from a higher realm that oversees the stars and Runeterra and possibly other worlds, 
may even end up being considered a celestial himself.
Riot has made this whole thing confusing with Targon having an interstellar empire, but then stating that Runeterra is big enough for them to tell all of their stories without exploring other worlds.
Interestingly enough 's story was extremely well done and I'd like to hope that Targon will be shifted in line with this newer concept of celestials going forward.
A Sol is not the only "alien" we have. Bard is an "alien" too. Zoe, Leona, Diana, Tarik and Pantheon are arguably at least part alien as well.
Well... There is a very alien look alike champion that is long forgotten simply becuase they were cancelled.
http://pm1.narvii.com/5944/700a33de7548dbe8229eeeab4b308927c2c9647d_00.jpg
Taric and Malphite were originally pulled over from another world. So were Kayle and Morgana.
I'd like an alien champion. And I have just the design in mind, too! Cosmic waifu let's gooooo! https://staticdelivery.nexusmods.com/mods/110/images/36188-2-1379482394.jpg
_ "The depths of space crawl with terrible entities. Pray they ignore this world."_
To me, that line was always referring to the Dark Star, especially the latter. There's also the fact that Sol isn't the only one of his kind and he has sisters if I recall correctly.
Or that was just a refference to the old Darkin role which was updated and so ahould that line.
Maybe they can be his siblings. Swain does have a line where he says “what is this about...siblings”
