The Immortal Bastion, Mordekaiser, Elise, and Swain
https://i.imgur.com/JjFH824.jpg
The Immortal Bastion in the old lore was a fortress built by a "Revenant" of great power. Tribes united against him and defeated him, forming the nation of Noxus. In the new lore this revenant was Mordekaiser himself.
Morde's bones were kept in the fortress until his skull was stolen and brought to the blessed isles. Those isles became the Shadow Isles and his Liches brought the rest of his bones to the isles. Now Morde lives on the isles, but still wants his fortress back. But the Fortress still has a connection to the Shadow Isles through The Black Rose.
Elise serves Vilemaw the Spider God and trades lost relics from the isles with Leblanc in exchange for Black Rose members. 
Does Mordekaiser know this?
And is there a way he could use her as an agent to put him back on the throne? I mean if he ruled again he could promise Vilemaw endless numbers of the living to consume -although he would use most for his undead armies.
Then....there's Swain.
Swain's parents sought a demon that lay within The Immortal Bastion
They sought a power, a shapeless voice cackling in the darkness of the Immortal Bastion. Something like a raven’s caw…
And that power sought Swain out. But why?
As he lay on the verge of death, a raven approached to feed, and Swain felt an old, familiar darkness press upon him again. But he would not let it take him. He could not. Staring into the the bird’s eye, he saw reflections of the evil strangling the heart of Noxus. A black rose. The pale woman... and her puppet emperor. Swain realized that he had not defeated the hidden cabal, and they had betrayed him to what should have been his death, after seducing Darkwill, the man they failed to overthrow. All this was glimpsed, not in the mind of a raven, but something more. The power his parents had been seeking, the demonic eyes blazing in the dark…
This doesn't sound so much like a "realization" as something psychic. In D&D terms it sounds like he passed a Will save and maybe even reversed the effect onto the bird. But does this sound like the demons we know?
Feeds on misery,
feeds on pain and suffering. But what then does Beatrice The Raven feed upon?
Cast out of the military for his “failure,” considered nothing more than a cripple, Swain set about uncovering what truly lay within the Immortal Bastion—an ancient entity, preying upon the dying and consuming their secrets, as it had attempted to consume his own. Swain stared into that darkness, seeing what even it could not: a way to wield it.
The demons we have seen prior all fed on some human emotional energy. But secrets....are something different. What's more, why did it take up residence within the Immoral Bastion? Was it....imprisoned there originally by Mordekaiser perhaps? Or was it drawn there by the dark magic dealings of The Black Rose?
That aside Swain originally knew nothing of sorcery -he was no mage or necromancer. How did he manage to learn more about what took up residence there? How did he actually learn to control it and how did that work?
Never make a bargain with a demon that you intend to keep."
And what bargain did he make? What did he offer and how did Swain turn the "deal" around on Beatrice?