Ascension - What is it?
So, now long after the Shurima Event, I got to the question: what exactly IS "Ascension"?
All we know is that it is supposed to be an empowerment ritual used in old shuriman times while using the energy of the sun. But how does it work? Are there downsides to it? If it was so awesome, why wasn't every Shuriman an ascended? Are there possible side effects? And, of course, could ascension be replicated by "modern" methods? (aka Hextech/Techmaturgy).
I will be talking about six champions here:

Yes, I know Cassipaia is cursed and not ascended, but I will get to her and her curse since it might be an interesting topic that might be connected to this. And about Twisted Fate... I'll explain that later.
So, about the first three. At first it seems like ascension doesn't turn you into a generic magical super-human and there seems to be some individuality. But how does it work? Does a popup plop up in your mind the moment you ascend, asking you to choose appearance and distrubute skill points? Not very likely. It seems like ascension turns you into what you think you are. Sounds weird, but let me explain.
It's very likely that the Shuriman Ascension technology was shrouded in mystery and religion, even for the shuriman people. So maybe some thought that it would turn people into gods or make them equal to gods somehow. Now, let's imagine that the highest god resembles a bird-man. So what form comes first to mind if an emperor thinks of becoming "a god"? That bird-man-god. Azir views himself as the "Emperor of the Sands" - what is his power? Sand control.
It's very likely that the same thing happened during Nasus' and Renekton's ascenseion. During the process they identified themself with their gods who were closest to their profession and turned into something that was similiar to how they imagined them.
Xerath on the other hand... is what could be called "true ascension" - because of his desire for ultimate freedom he just got that: being free of everything, even of a mortal body. He didn't want to become something "similiar to a god", he just wanted to be "free" - quite fitting for a former slave.
Now, why did I list Cassipaia before? Actually it's quite simple. If the appearances of ascended/half-human beings show their "true being", how would the people of Shurima react to someone with the body of a snake - an animal that has probably quite some bad reputation there?
The cell where Xerath and Renekton where held was secured with a defense mechanism, made to scare people away.* "If you open this tomb and free the evil inside, all shall know that YOU were the one who betrayed Shurima and sided with the traitor"*. I can imagine the snake curse being some form of "highest possible punshiment" in shuriman law, since it's basicially an excommunication from society - who would help someone branded as a traitor?
Ok, and now to Twisted Fate.
Empowerment through ritual? Check. Ritual conducted by a guy who's some kind of magic-pro? Check. Said pro is called Xavier Rath, what sounds awefully close to "Xerath"? Check. Possibility for a being like Xerath to use illusion magic and blend in with modern society? VERY HIGH.
OK, but why would Xerath be interested in replicating the ascension ritual? One possibility could be the hunger for more power, trying to ascend even further. Another one could be "I lead the world to absolute freedom, EVERYONE SHALL ASCEND AND BECOME IMMORTAL LIGHTENING BLOBS LIKE ME!" - we should keep in mind that we have no idea what Xerath is planing since he left the tomb. Or maybe he's just playing a bit of "mad scientist", we can't know that.
But why isn't Twisted Fate a half animal or some form of sentinent blue light? It's simple, because Twisted Fate never asked of being turned into that. All he wanted was magic, and that's what he got. He might be immortal though, but how would he know? For that he would needs his powers for some decades to realize he doesn't age.
Tl;dr: Ascension seems to be bound to the subjective expectations to the result of the ascending person. Also: Beware of people with suspicious names.
Your opinions on this?
and his people may be an early example of it. In his story, his people were harassed by some malevolent being/creature. Gnar stood up and went berserk to defend his kin. He may have been his kind's ascended. They may have used what they knew about ascension to give one of their heroes the power to fight off this creature and thus Gnar became ascended. Gnar is the only one known of his kind to gain tremendous power like that and lets not forget that he is somewhat immortal. Even being frozen for a millenia didn't kill Gnar where other living things would probably die due to cellular ruptures from ice crystals expanding inside their cells.
may have used some form of ascendancy to become powerful too. Their method may have differed or not as they locked their power to some sort of weapon, but even the living sword of Aatrox may very well be a manifestation of his power into a physical item.
is because of genetics. Notice how when Nasus, Azir, and Renekton ascended they took on a different shape and species. The only thing that can bridge two species together in Runeterra that we currently know of is Ascension or some derivation of it. Shyvana could be the product of some partnership between humans and dragons long ago. To give some proof to this, I will employ the Dragon Slayers. Dragon Slayers were powerful humans who hunted down and killed dragons. Dragons, in Runeterra, are intelligent creatures. Shyvana's father and his followers may have tried to broker a truce to stop the hunting and unite both species through some ascension. Now I do not want to continue this much with more speculation, but I will add this about Shyvana: Some within her father's kind(dragons) may not have liked the truce and the product(Shyvana), so they branded Shyvana and her father heretics. Not everyone has to like the same thing, just like how Zerath saw no wrong in his Ascension, others thought about it as heresy and betrayal.
He's the product of pissing of Soraka... it's a curse, similar to Cassiopaia's. Let's think a moment. Shurima Tech seems to utilize sun-energy. The sun is a star. Soraka is the "Starchild". Soraka's curse on Warwick might be the VERY SAME thing that happened to Cassiopaia - just much, MUCH stronger, his tranformation slowly eating away his human mind. She cursed him to make him "look as corrupted as he is inside".
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