Notes1: Based off the presumption first mentioned in At Every Crossroad, A Menhir that Fel is the ultimate summation of Light (which sees only one truth and denounces all other paths as lies) and Void (which sees all possible paths as the truth but speaks in half-truths); therefore, by following this particular line of thought, Fel would see the actual truth of what is truth and what is a lie. It also plays into the idea that Illidan saw not only the Legion marching across the cosmos bringing ruin to every planet that harbors a slumbering world-soul but gleaned Sargeras's method for doing so - it being wiping reality clean so the Void Lords have nothing to twist and corrupt. This is also written as a response to Illidan's article on TvTropes, which states that he's shown no indication that he doesn't care in the slightest about the Void Lords. Which...could be true, if you argue in favor of it, since he clearly states to Xe'ra that the Legion's end is all that matters to him. However, if we go with the theory that Fel is the truth of everything - that is, being truth without lie - and the aforementioned idea, then it can be argued that Illidan does care and that the only way to protect Azeroth from the shadows that threaten to consume her is to be within the shadows (i.e. the Seat of the Pantheon in the Great Dark Beyond) and beat it out of Sargeras the old-fashioned way. There's nothing so far that shows this is the case outside of it being tinfoil-styled headcanon/speculation, so take this story for what you will. (Then again, Illidan is notorious for playing the long game and not telling anyone his plans, so chances of this being true is fifty-fifty.)
Third: It plays off the very obvious assumption that in the far future, Illidan, Sargeras, and the Titan Pantheon will be freed from the Seat for when the Void Lords play a more active role in World of Warcraft. I don't think there has ever been in a story in the history of entertainment that has a hero or villain sealed away and never wake up/see the light of day ever again for all eternity (because you just know if there is enough popular demand for it, they are going to come back). The only story I can think of where this does occur is Mother 3 (although Porky is very much awake); according to Shigesato Itoi, even after the world ends 5.5 billion years later, Porky will still be locked away in his Absolutely Safe Capsule, trapped (and perhaps content) with what may be seen as his own self-made paradise of isolation for all eternity.
A minor note: This was going to have a short flashback scene referencing Turalyon's outrage at Illidan destroying Xe'ra, but when I had thought it over it started to sound too much like Obi-Wan's short speech to Anakin on Mustafar in Star Wars: Return of the Sith (it even began, word for word, with Turalyon saying "You were the Chosen One!" to Illidan). While it was meant to flesh out the scene presented in "The Rejection of the Gift" cutscene, I scrapped it from the finalization, thinking that if I should return to reflecting on that particular scene again (and I probably will) I can do it in a way that won't sound like it was ripped right out of the movie (not that I think Illidan would hate Turalyon for trying to come at him; he outright says that his faith in the Light blinds him, a factor that comes into play in the Arathi Warfront when he confronts Liadrin and calls her "misguided" (compared to the earlier builds in BfA's alpha where, IIRC, he said she was "an evil paladin").
"It's been a long time, Sargeras," Illidan says. "Too long," he almost croons, and his heart soared with warm, dark delight at the very quick, very minute way the Dark Titan stops trying to pick himself up off the floor. Pauses to glare a promise full of rage and murder at him.
In the end it doesn't matter if he's on his knees, standing up, up on his belly or on his ass; he's not going anywhere. "How long has it been, do you reckon? How long did you sit idle, waiting for that one sweet moment where you could have scoured all life from the face of the earth? Would you care to take a guess?
"Ten thousand," he adds, without preamble. "Ten thousand years have passed. Time and time again you have tried, always thinking it was the right moment...only to fail. Tell me, Sargeras, did you stop to think there was ever a right moment for anything?"
No, he thinks, seeing the way the Titan's lips curl into a vicious snarl. No, he has never considered the notion that everything he did in his eternal life was done for the right moment...but that everything he did was, in his mind, right, damn the consequences. So long as it set back the Old Gods and the Void Lord, he would do whatever it took to purge the universe in felfire until not even the stars remained and only the silence of eternity would persist.
That is, until life took root in the Great Dark. Bloomed, flourished, and wither under the soft, swift, harsh caress of time and Void.
The Void, whose reach is infinite.
The Void, whose influence is eternal.
Intangible. Irremovable, as is the Light.
The sound of a croak perks his ears up, steadies himself even as his hands reflexively tighten around Azzinoth's handles, but Sargeras doesn't move so much as straightened up a little more from where he's kneeling. He simply glares, expression made all the more awful from the fel-lined cracks that spiderweb his face and trail down his neck into the folds of blistering, scarlet-black armor. "You already lost," he says, voice low and sandpaper-rough. "When they finally come, only the shell of her cold, grey soul will be theirs to feast upon."
Sargeras smiles grimly. "You will wish you had never denied me, Betrayer. Without me, you and all your heroes have hastened Azeroth closer to her doom. You have lost, and you have no one to blame but yourselves for all that shall transpire in my absence."
"Life will find a way," Illidan tells him, and that, at least, is something he agrees with Malfurion on. Alliance, Horde, and third-party factions are always going to have their petty squabbles; what they do and how they respond is solely on them. When there's a threat that grows from within or comes from beyond the Twisting Nether that puts the fate of the world into focus, they would set aside their differences and band together to do away with the darkness and cruelty that attempt to destroy everything they hold dear and the countless years of history and culture that has been established, torn down, and built upon time and time again.
But the darkness will always exist. If there is a creature more ruthless than the Void and more righteous than the Light, it is the people of Azeroth. They are what have stopped him, the Scourge, the Iron Horde, the Old Gods, and the Burning Legion from doing what they believed was right for the future of the world and the cosmos.
Now there is but the Light and the Void to contend with...and themselves, for who can stop the other when there is nothing left to pry them apart?
The people of Azeroth, a voice echoes in his mind. Her Champions. People from all walks of life and differing beliefs. Without them—them, not Alliance or Horde—Azeroth would cease to exist. They are her future. They were numerous, almost seeming endless with the stories the Illidari and their de facto Slayer had regaled to him upon the Broken Shore. One of those heroes stood out the most to him, and this one he sent a message to alongside those in the crystals he delivered to Malfurion and Tyrande prior to boarding the Vindicaar. It is this person he has the utmost faith in doing what is best for Azeroth, and it is this person he believes will rise above the factional headbutting and close up the wound that is spilling the world-soul's lifeblood across the planet.
This one will be the vanguard against the shadows, against the daylight, against themselves.
People tend to forget that the darkness of creation lies more strongly from within more than from any eldritch abomination lingering beyond the scope of reality.
From whence death is brought through a cycle of hatred, there is renewal in a cycle of enlightenment.
People learn and forget. The knowledge to avoid needless violence may stay in their minds; it may not, and if it does not, life, too, will find a way to remind them.
But this Champion of Azeroth, Illidan thinks very briefly as he swings the blades into reverse grips, no matter the ties to the past, will do the right thing: Fight-in blood, in sweat, in tears, in rage against Light and Shadow, Life and Death, and the marshaling might of Alliance and Horde.
Let them come. They will all know how far one person will go to defend the world.
He smirks, not so much at the thought of a young child going to war against creation and government but at the sight of the Dark Titan—shrunken to mortal size but still huge—standing on his own two feet without falling. "You dare?" he challenges, amused.
Sargeras scoffs and straightens to his full height, which stands taller than half of Illidan himself. "You had such potential," he growls. "A pity you had to go and waste it. You could have been so much more."
His ears twitch, and then a memory, come unbidden: of the Prime Naaru and her soft, gold-white light, of the warm relief in her words of at last meeting the Child of Light and Shadow alive and well after falling in the Black Temple. They did not know any better, she had said. They had thought they were doing the right thing. Yet the world needed a hero. Azeroth needed her Chosen One, and her people needed him to guide them across the stars to where the Legion rested upon their Burning Throne. What the little children could do as a group, he could do with the strength of Titans.
The Light, shining as a diamond upon his brow.
His scars, erased, and his body filled with the joy of creation.
There would never be a more beautiful person like him. Never would he have to suffer from his sins again. He would be the First and the Last of the Lightforged, the Chosen of the Army of Light. Turalyon knew it—poor, simple Turalyon, eyes Light-touched and smiling angelically as he presented him to Xe'ra. The time had finally come. This was the only way. The right way.
How wrong they were, and how wrong she was.
Velen knew it then, when her pieces scattered across the deck. So did the Exarch's paramour, but she was simmering with the dark power, and as Xe'ra's light was snuffed and the shadows flooded back in did the subtle around the woman emerge a little more strongly, as though it was glad to have come out of hiding. Both were surprised, but they did not fly into the rage Turalyon did.
They knew. So would he, and in time, they would know more what the Light intended for them if they did not follow.
These scars are mine. This is the power I earned at the cost of freedom.
He glares at Sargeras. "Whatever future I had before that day, when I came to you, has long since passed. This is the life I chose, the power for mine to use at my discretion, for one single purpose: to see the Legion's end, and deal with you. Lord Sargeras."
Sargeras grins. "You dare?"
"Yes," Illidan croons. "I dare. From now until the end of time, for as long as it takes for this prison to hold, I dare. The battle may be won, but the war is far from over; it's just getting started."
"You have damned Azeroth, boy," the Dark Titan says. "You have opened the way for the Void. Have you no sense of shame for what your actions are about to bring about?"
Illidan laughs, a high, growling rumble welling up from the depths of his chest. It's the kind of joke one would hear at a bar that catches them completely by surprise. It's the kind of joke that's supposed to be witty when it's not. "My actions? Have you not thought what your actions might just cause?"
"If I cannot have her, then no one can. Not the Void, not the mortals, not even me. I did what I thought was right."
"Aye," says Illidan, "as did I, as I will continue to do so now." He adopts a ready stance, blades catching the light of the stars and the glow of the Pantheon spirits that watch silently, thoughtfully, from their seats. Sargeras shifts, unarmed save for his teeth, his flame-licked body, and the horns on his head, and never has victory tasted so purely, sinfully sweet. "You have answers. Everything you have shown me from those visions, everything you have done in the name of the Crusade and your own desires...I want them. And I am going to get them from you, one way or another."
He charges, fel flames spewing from his tattoos and wings wide. Sargeras roars, sets his feet apart, and braces himself for impact.
(It is the first of many battles.
(But nothing lasts forever.
(This is only just begun, and until it finally happens, no one will ever know.)
