The Ruined king, Hecarim

Hecarim is the Ruined King of the Shadow Isles brought back to life by Karthus to kill the only person opposing the higher power in the Shadow Isles, Mordekaiser.

We already know that the Shadow Isles were once a thriving kingdom that fell when the king's daughter died, and caused it to become the cursed land of the dead. We also know that Mordekaiser betrayed the king in some way, and that way was not killing the king's daughter. If you rule out killing his daughter, there are only a few ways left that Mordekaiser could have betrayed the king. Either he killed the king himself, or he did something behind the curtains that helped the kingdom fall and become cursed. If it was the first one, why would the altar warn hecarim about Mordekaiser? He would know what Mordekaiser did. We also know that Mordekaiser's armor and undead status are a punishment or curse, that he seeks to get rid of for some reason.

When you really think about it, why would one death, the death of the king's daughter, cause an entire kingdom to fall, and become the cursed land of the dead?

So, great, what happened then? Fast forward a couple of centuries, Karthus enters the Shadow Isles, accepts undeath, and becomes a sort of god of the place with the "Keys to life and death". But wait, why a couple centuries? The events of the current Shadow Isles have actually taken a very long time to flesh out.Sometime between their creation and now, the beings Thresh(The soul collector) and Yorick(The gravedigger aka body collector) came into existence, and Yorick's lore states that he's been digging in servitude to the Isles for centuries.

The fact that they came to existence in the Isles through dying serves as proof to what Elise says about the Isles being death's gate. "That was when I understood that death was another world and I was at its door."

Hecarim's creation was shortly after Karthus gained his powers. The soul of the king was floating around the Isles along with all of the other souls kingdom's residents.Off tangent here, I believe the fog surrounding the Isles to actually be nothing more than the souls of the dead. When the king's soul was extracted to create Hecarim, it left the fog barrier weakened, and it is now Elise's job to offer souls in masses to try and strengthen it.

Many quotes and lore lines support Hecarim being the reincarnated king: "Remember who you once were, Hecarim!" - Riot's way of telling us he's important. "Mordekaiser is not to be trusted, Hecarim!" - The fact that Hecarim is the one receiving this warning is important. "others still believed him to be the creation of some hateful necromancer." - Straight from the horse's lore. Some hateful necromancer sounds exactly like a guy that hates the living and has the keys to life and death themselves.

Lemme know what you guys think :D

Tl;Dr No, pls read it.

EDIT: Upon hearing you guys' suggestions, I can definitely see it possible that Hecarim is actually the leader of the former king's cavalry/army. This could easily make just as much sense as my previous hypothesis :)

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