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Here's what the creators of the game said on the matter in the Behind the Scenes DVD (paraphrased a bit):

"Since she was a little girl, Cain's been roaming around this map looking for pieces of this prophecy of the End Days. All that while, he's teaching Leah to be his apprentice. He would have been constantly talking to her about this prophecy, you know, 'At the End of Days, Angels and Demons will fight on the land of Man' but she has never seen angels or demons so she doesn't believe it, but at the same time she closes her eyes and sees these nightmares and doesn't know if they are real or just her uncle's stories blending together."

"Leah eventually has to come to terms that everything he had been telling her was real, and she finally realizes that and starts fulfilling this and becomes this new Cain for us. Tyrael, as a mortal now, begins to rely on Leah as that Deckard Cain role. Together, they help pretty much uncover Diablo's maneuverings and what he's been planning under the surface of all of this all along."

So, yeah, she was basically the Sanctuary equivalent of an internet user screaming PROOF!!!!!!! or not believing that anyone, ever, could be related to or personally know someone 'famous.'

The worst part is at one point she specifically talks about dragging Uncle away from a horde of skeletons or something years? before the Metyrael falls, but those must have just been stories too.

I think that NPC is just random quest NPC_001 and not the Mystic.

http://www.diablowiki.net/Mystic
http://www.diablowiki.com/Mystic
http://d3db.com/news/id/43

http://d3db.com/npc/i/karyna
http://d3db.com/npc/i/myriam

I didn't believe that Diablo became Tathamet in the first place. I don't see this as possible within the lore. Following his death, the seven heads of Tathamet spawned the Great Evils. His headless corpse became the Burning Hells. I don't see how Tathamet could become whole again. If Diablo did transform into Tathamet, wouldn't he have been unstoppable? Wouldn't Sanctuary have burned? I don't think that anyone but Anu himself would be capable of stopping Tathamet. Plus, if Diablo did become Tathamet during the events of Diablo III, I'm sure that they wouldn't have left us guessing. Shit would have been explicitly stated during the narrative of Act IV.

Yeah that's one thing that they did kind of strangely, hyping Diablo as the Prime Evil and this super mega badass. On other forums, I've seen people saying things like 'lol how can there be an expansion, we killed the prime evil' 'yeah right, we killed the prime evil and now we gonna fight the sin lieutenants or something?'

They should have done a better job of explaining what exactly the Prime Evil was in context of Diablo's 'prime evil' aka all the evils in his body. (Or Leah's body I guess technically ) Especially since they have Tyrael randomly mentioning Tathamet (which like you said, should have roflstomped whatever went against him, unless we are to believe one Nephalem is that powerful) when asked what the Prime Evil refers to. I guess that may be intentional though, as it seems 'prime evil' seems to refer to a few different things, like in that quote from one of the devs the 7 Evils are all 'prime evils,' the 3 brothers are also the 'prime evils,' then of course the 7 Evils in one body is the 'prime evil' and Tathamet was the original Prime Evil.

I'm not sure if it ended up in the game, but in the beta files Diablo had bunch of curses from the other Evils:

Diablo_CurseOfAnguish_name Curse Of Anguish
Diablo_CurseOfDestruction_name Curse Of Destruction
Diablo_CurseOfHate_name Curse Of Hate
Diablo_CurseOfPain_name Curse Of Pain

Adria has undoubtably been lying through her teeth. We shouldn't trust anything we have heard from her. I went from loving Adria as a character in Diablo to despising her as a character in Diablo III. I can't wait to embed a knife in her skull with my DH.

I don't think that we know what is going on at all. I think that the expansions to Diablo III are going to blow us away. I'm hyped as fuck because I am dying to see how this shit plays out.

Thank you for the insight. You know, this is exactly why I joined DiabloFans in the first place. I've been craving lore discussion such as this for a long time.

Lastly, Pyrrhic, you should read Diablo III: The Order by Nate Kenyon.

I'm definitely looking forward to the expansion, not just for the inevitable new features, but to see where this story is headed. Sucks that it is likely over a year away still, but we'll probably get some info on it sooner than that. (Probably will get the name first via trademarking like with Mists of Pandaria, a 'blue' then saying "Well, usually when we trademark names like Diablo 3: Queen of the Abyss, it's for a Diablo series book or comic." and then the official press release comes out a bit later confirming Queen of the Abyss or whatever is the expansion.)

At least with DiabloFans, you know the people here should be, well, fans of Diablo, and if they are wandering into the Lore & Storyline forum, they should be interested in the lore and story. As I mentioned earlier about the 'other forums,' other night I looked at a 'what will the expansion be' topic, and they were discussing why Westmarch is more than likely going to be a setting (which it seems is probably 98% chance that it is, unless they pull a fast one and just happened to have 2/3 followers have strong ties to it, with their plotlines both ending with them wanting to go there or you going there with them) and saw some jagoff saying something like "lol u guys probably think the stuff ur foloowers say is releveant too." (Which is hilariously stupid, especially when you watch that Behind the Scenes thing about how they went about telling the story while still letting it be a fast-paced game, and how they wanted the followers to be involved characters.)

I'll probably pick up the Diablo books at some point, but currently I am reading WW I era or earlier books since I've always found the Great War intriguing and most of them are free for my Kindle.

Quote from GeNMaKB

I am glad that my topic has spawned such excellent discussion. I do not have the time to read through everything right now (fucking dentist) but I will later tonight. My interest is definitely piqued. From what I have read of your post already, Pyrrhic, you deserve a +1. It is nice to know that there are people out there that find the lore of Diablo as interesting as I do.

Edit: I thought that the souls of Mephisto, Diablo and Baal were trapped in the abyss, following the events of Diablo II: Lord of Destruction. How did Adria mark their souls for capture within the Black Soulstone?

In the Behind the Scenes DVD, they talk about how they were throwing around ideas for what to do with the story, and they decided that since the Dark Exile, Diablo has been conspiring to kill off the other Evils and unite all their souls into one body, his body.

Paraphrased a bit for some quotes (bold is my emphasis):


"Leah represents innocence. Leah represents hope. She is smart, she is resourceful, she has powers of her own. She represents everything that humanity can be."

"What happens to Leah is sort of the ultimate tragedy and is what is going to happen to everybody if you, the player, doesn't stop it."
(The people will die, or they will become hosts for demons/corrupted...?)

"One of the guys had this idea for this kind of cool NPC girl you meet out in the woods with a bow, and there was some suggestion, that she might have been the daughter of the Wanderer from Diablo 2"

"Her mother was the witch Adria, Adria was a character that occurred in Diablo 1. I think we look at her as this woman who was obsessed with the occult, the arcanum. You know, chasing mysteries and magical powers over the course of her life."

"She meets with the Dark Wanderer and falls in love with him, and at this point he has been corrupted by Diablo, and she bears his child, and this child is Leah.."

"It was clear that she was not fit to be a mother, and potentially she had her own dark mission, such that Adria gave up Leah for adoption."

"Ultimately it was Cain that recognized this baby was very special and kept her safe for the past twenty years."

"He potentially knows that evil is lurking within her, but because he carries so much guilt from the past games, trying to help people understand that the sky is falling, and not really taking action, he felt he needed to take her on and raise her the right way. And on the other hand, he knew if this girl so much as looked sideways, he knew it would be his job to take her out."

"Since she was a little girl, Cain's been roaming around this map looking for pieces of this prophecy of the End Days. All that while, he's teaching Leah to be his apprentice. He would have been constantly talking to her about this prophecy, you know, 'At the End of Days, angels and demons will fight on the land of man.' but she has never seen angels or demons so she doesn't believe it, but at the same time she closes her eyes and sees these nightmares and doesn't know if they are real or just her uncle's stories blending together."
(Yep, called it that the End of Days isn't fully manifested )

"Leah eventually has to come to terms that everything he had been telling her was real, and she finally realizes that and starts fulfilling this and becomes this new Cain for us. Tyrael, as a mortal now, begins to rely on Leah as that Deckard Cain role. Together, they help pretty much uncover Diablo's maneuverings and what he's been planning under the surface of all of this all along."

"In trying to solve this riddle of how Diablo comes back again, we kind of had the idea that maybe this time he comes back through his mortal offspring."

"All the way back to the Great Exile, this has all been Diablo's plan. At a certain point he discovered the idea of the Prime, the idea that all the Evils can become one, and become exponentially more powerful than they had ever been before, and that essentially the last 300 or so years have been his plan to off all the other Evils."

"For the first time all the essences of these 7 prime evils now, go into Leah and she turns into Diablo and becomes the one prime evil."
(That's a direct quote, confirming that the Diablo in game was not the Prime Evil aka Tathamet, and just all the 'essences' supercharging Diablo?)

"It fits with a lot of the stories that were told in the original Diablo and Diablo 2, where we see really precious characters succumb to this kind of corruption and madness and evil, and so this was an opportunity for us to take a character that a player directly interacted with, and hopefully that the player really likes, and see that exact thing happen to her. It was just too evil for us to resist."
(Must have been fun compiling this story, wish I could have been on that team. )

"To see her father Diablo take her over and turn her into a demon lord is the greatest tragedy we could think."

"It's tragic what happens to her. But I think the truth of Leah is she's innately heroic. She's a good person. But this evil was rooted at a genetic level. And the turn that her life takes was inevitable to some great degree. When ultimately her turn comes, it feels terrible. We want you to feel like you've been socked in the gut, like you know, "anyone but her." Her spirits still out there somewhere. There's a good girl there that deserves to be saved and brought back from the Abyss. While we don't have any clue yet what subsequent chapters will be, a couple clues (Metzen winks), I'd bet that we would chase that down because it feels right from a story level, and it feels right from a character level."
(Covetous Shen: Do you think that Leah is lost forever?
Player: Diablo consumed her. She is gone.
Covetous Shen: Do you not think Leah's soul is stronger than that? But, oh, but then sometimes I-I forget that you have not seen everything that I have seen.)


So this is Diablo's plan he has been going after for centuries. The whole 'Adria marked the souls' thing? Well, for one, do we actually trust her at her word? No, not after what she does and the fact we have been 'played like a fiddle' by Diablo the entire time.

For all we know, Izual could have been the one that rigged up the Black Soulstone. Or Zoltun Kulle, who the other characters pretty much drilled into our skulls was untrustworthy, set it up himself to suck in the big boss Angels and Demons and feigned surprise to try and get us to let him use it on his own. Or the Evils/Diablo themselves at some point, since as far as I know, the events of Diablo 2 were the first time they had ever been 'smashed' and Tyrael was likely the one that thought smashing their stones would send them to the Abyss. (The same soulstones we know were flawed and used as tools by the Evils, thanks to Izual)

Tyrael's my man, but like he says in the game:

Angels do not, in fact, know everything.

I'd have to look for a precise timeline/in-game dialogue, but:

Tyrael:Three hundred years ago, I selected Kulle and six others to form the Horadrim. He was a great man who was driven mad with his long quest to hunt evil.
Player:
Tell me, why did the Horadrim have to kill Zoltun Kulle?
Tyrael:
He delved into powers not meant for men, trying to fashion an artifact that could fill his empty heart with the souls of angels and demons. The Horadrim had no choice but to slay him. The order... never recovered.

So potentially, the Black Soulstone may have been around for hundreds of years, around the same amount of time, as stated in the BtS quote above, that Diablo has been planning his big 'middle-finger' to his brothers and sister. Again, would have to look up references, but now is possibly the first time in centuries the Evils were ever vanquished, since the Primes were running amok on Sanctuary and the Lessers were chilling in Hell due to the Eternal Conflict going to a standstill as all eyes focused on Man.

Although the Great Conflict burned hotter and longer than any of the stars in the sky, neither side could gain dominion over the other for long. Both factions sought some way to turn the tides of the war to their favor. With the ascension of Man and his mortal realm, the Great Conflict ground to a mysterious halt. Both armies paused in a breathless stalemate, waiting to see to whose side Man would eventually turn.

So, it is possible that the souls were 'marked' centuries ago, and Adria was just making sure all the pieces came together, like getting Deckard Cain out the picture, guiding the Nephalem hero to find ZK's bits, making sure Belial and Azmodan got the kibosh put on them, etc.

D2:LoD's E3 2001 trailer is the source.

Edit: I would interpret it as he wanted to use the Worldstone to make himself fully manifested as a demon (somehow) and not merely himself possessing and warping Tal Rasha's body.

("The Prime Evils, weakened and bodiless, were banished to the mortal realm where Azmodan hoped that they would remain trapped forever."

"The power of the Soulstones proved to be much more difficult to employ when used against the great Prime Evils. Voraciously disposed to possessing hapless mortals, the Three Brothers found that they were immune to the effects of the Stones while occupying human souls. Sadly, we were forced to hunt down and kill the innocent victims of the Prime Evils so that their demonic essences could be subject to the effects of the Soulstones."

"The body of Albrecht, fully possessed by Diablo, began to distort and change. The small boy grew and his eyes blazed as tendril-like spines ripped through his flesh. Great, arched horns erupted from Albrecht’s skull as Diablo altered the form of the child to match that of his demonic body.")

Baal wanting to be the sole ruler is also not surprising, as all the Evils seem to want to be the 'big man on campus' (despite them coming from the heads of a hydra dragon thing where they would have had somewhat equal power, presumably) and like Tyrael says in the game:

Still, the day might have been lost had the demon lords not fallen to fighting amongst themselves. So confident of their impending victory, they turned on each other over the spoils they had yet to win.
I shudder to think what the demon lords might accomplish should they ever stop betraying one another. Such is the self-defeating nature of evil.
...
Always before, the Lords of Hell bickered and worked against each other. They undid themselves.

Baal's goal according to Tyrael was to manipulate the Worldstone to force mankind to his will.

Tyrael:
Baal, the Lord of Destruction, sought to enslave mankind to the power of Hell by corrupting the sacred Worldstone. Unthinkable though it was, I was forced to destroy it.
Player:
And much of the north with it.
Tyrael:
Understand, friend, that entire worlds burned as Heaven and Hell fought over the Worldstone. Arreat's destruction was regrettable. And, believe me, I paid a high cost as well.

I think most of the 'how the Worldstone works' is in the book series, which I haven't gotten to yet, but it's possible Baal's true intent was to craft his own world where he was the ruler. (The map of Heaven in the CE artbook has a tower structure labelled 'portals to other realms.' There are multiple towers, too, but those may mean more like High Heavens/Hell/Trag'Oul 'realms' and not worlds like Sanctuary)

A possibly more likely solution was that according to D2 lore, breaking the soulstones would prevent the Evils from "manifesting in this world ever again." Since Baal would knew Diablo and Mephisto got smashed, he would have been the 'last man standing' on Sanctuary. (Apparently confident that the Angiris Council wouldn't care except for Tyrael, and that the remaining Lesser Evils would leave him alone, which it turns out was exactly what Azmodan desired at one point in the series' history:

Azmodan believed that with the Three set loose upon humanity, the Angels would be forced to turn their focus upon on the mortal plane - thus leaving the Gates of Heaven abandoned and defenseless.

)

Quote from Ranim

I wish the whole game turned out to be a carefully orchestrated illusion where you really did go to those places, but what you saw was different, and you were the one who killed Cane, and you were the one who Injured Imperius, and you fought at the wall and defeated Azmodan, as an unknowing agent of Belial. That would make the mess we're left with brilliant.

Everything you see is what they want you to see. Everything you do is what they want you to do. Everything you think you know, is a lie. Nephalem, you are indoctrinated.

That would explain why the big evils and their goons have suddenly developed holo-com technology to broadcast their plans at the Nephalem hero. ("Oh, uh I totally saw this dude using an amulet, so I stole it, yeah, that's what I did.")

Hmm, the Wizard thinks some book had them as this hero of Prophecy. The Demon Hunter had their family killed and a group of hate-filled killers recruited them. The Witch Doctor was sent on his quest by the spirits? I don't remember the Barb/Monk pre-story, I think the Barb was looking for the ultimate challenge or something.

Expansion starts with a cinematic of Deckard Cain and the surviving Diablo 2 heroes ripping you out of a demonic torture chamber. "By the Light, what have those fiends done to you? At last, I was able to decode some of the ancient Horadrim prophecies, which led us to you, but I fear I may have been too late. Dead? No, my friend, I can assure you I am quite alive! However, if we do not act swiftly, I am afraid we shall all be headed for the Unformed Lands! "
You stagger forward, eyes set on an open doorway with sunlight pouring in in the distance. The sounds of battle echo off the caverns walls. You fall to your knee, a tired-looking Amazon and sullen Druid support you as you shuffle towards the exit. The camera pans out over a devastated wasteland down below, a horrendous battle is waging. The rivers run dark with the blood of the fallen, the bodies of angels, demons, and men, litter the ground as far as your eyes can see. In the skies, the angels and winged demons clash in a beautiful display of aerobatics and death. The poor souls that are wounded and sent earthward in this deadly aerial battle are torn apart by the frenzied forces on the ground.

You stagger back from the doorway, a bright light shines behind you and you feel an armored hand grip your shoulder. The Archangel Tyrael, Aspect of Justice, looks at you with the black void that is his face, "Nephalem, I do not know what lies the demons have been feeding you, but we haven't much time. The final battle is upon us, whoever triumphs on this day shall be the victor of the Eternal Conflict. Come, Nephalem, the hour of your true destiny is at hand."

"Corruption has the strength of deceit, but innocence holds the power of purity." - Adria, Diablo

Is Adria just a 'cultist' or corrupted mortal, or is she something more than that?

I'm skeptical that they were planning it way back then, but the townsfolk in D1 cast her as a super duper magic user, or something not human.

Why don't that old crone do something for a change? Sure, sure, she's got stuff, but you listen to me - she's unnatural! She doesn't eat or drink, and you can't trust somebody that desn't drink at least a little.

The witch, Adria, is an anomaly here in Tristram. She arrived shortly after the Cathedral was desecrated while most everyone else was fleeing. She had a small hut constructed at the edge of town, seemingly overnight, and has access to many strange and arcane artifacts and tomes of knowledge that even I have never seen before.

Adria is wise beyond her years, but I must admit - she frightens me a little. Well, no matter. If you ever have need to trade in items of sorcery, she maintains a strangely well-stocked hut just across the river.

While I use some limited forms of magic to create the potions and elixirs I store here, Adria is a true sorceress. She never seems to sleep, and she always has access to many mystic tomes and artifacts. I believe her hut may be much more than the hovel it appears to be, but I can never seem to get inside the place.

Adria truly bothers me. Sure, Cain is creepy in what he can tell you about the past, but that witch can see into your past. She always has some way to get whatever she needs, too. Adria gets her hands on more merchandise than I've seen pass through the gates of the King's Bazaar during High Festival.

Doesn't eat, drink, or sleep allegedly, able to get whatever she wants, most of the town is scared of her.. She seemed to know a lot about what was really going on too.

"No Mortal can truly understand the mind of the Demon. Never let their erratic actions confuse you, as that too may be their plan."

"There are many artifacts within the Labyrinth that hold powers beyond the comprehension of mortals. Some of these hold fantastic power that can be used by either the Light or the Darkness. Securing the Anvil from below could shift the course of the Sin War towards the Light."

"This is a place of great anguish and terror, and so serves its master well. Tread carefully or you may yourself be staying much longer than you had anticipated."

"You will become an eternal servant of the Dark Lords should you perish within this cursed domain. Enter the Chamber of Bone at your own peril."

"The Heaven Stone is very powerful, and were it any but Griswold who bid you find it, I would prevent it. He will harness its powers and its use will be for the good of us all."

So since we now know she was apparently an agent of Diablo, we can assume she was there to make sure things went according to plan. What is this plan?

From the D2:LoD instruction manual:




That was from something called Prophecies of the Final Day by the way.

Druid lore excerpt:

They created a new culture and language, cutting themselves off from their Barbarian cousins and their ways, vowing not to return to the Steppes of Mt. Arreat until the time of the Uileloscadh Mór, the final battle between the men of the world and the demons of the Burning Hells.

At the Túr Dúlra, the greatest of the Druid Colleges, stands the magnificent oak Glór-an-Fháidha. This tree is the most revered source of the Druids guidance and teachings. Under its branches, for centuries, the Druids of Scosglen have been honing not only their powerful arsenal of natural magic, but also the martial skills they have retained from their Barbarian forefathers. They have done this because they believe themselves to be the world’s last line of defense when the time of the great conflict comes, a time they believe is at hand. Lashing out in fury at the recent insurgence of denizens of the Burning Hells, and at the Leathdhiabhala, demonic corruptions of the very creatures they have vowed to defend, the Druids have, at last, emerged from their forests, marching toward their final stand against the minions of Chaos.

In D3 we have the Prophecy for the End of Days, which is a 'warning about Hell's ultimate invasion of our world,' and the pieces of the puzzle mentioned in it seem to be coming true. We were also supposed to learn why the Hells didn't invade 20 years ago in the game.

And at the End of Days, Wisdom shall be lost (Malthael being gone, or the mortal Tyrael's demise in X1?)
as Justice falls upon the world of men. (Obvious events of D3, or that Tyrael became aspect of Wis., leaving Justice to Nephalem)
Valor shall turn to Wrath - (Imperius raging over Hell invading, or Imperius waging war on the impudent Nephalem)
as all Hope is swallowed by Despair. (In-game events, or tied to the above, Imp's betrayal. sends Auriel into despair)
Death, at last, shall spread its wings over all -(All these lines reference angels/aspects, Malthael returns as Death?)
as all Fate lies shattered forever. (In-game event of the Hero 'shattering' the fate that Heaven lost that day, or a future event where Ithereal gets destroyed, probably by Malthael/Imperius)

So we know the culmination of this storyline, which they have claimed will get resolved in D3, is this final battle/ultimate invasion of Sanctuary by Hell. Something that has been prophecized for centuries and something that the Evils themselves seem to know all about.

I think Diablo/Evils knew what would happen in D3 as well, I forget what he says exactly but why would he send Adria away to be used later if he, and the angels, were sure he would succeed in the attack on Heaven, since it was kind of 'written in stone' on the Scroll of Fate?

My answer, he wouldn't, he knew he would be stopped, in fact, he and Belial/Azmodan wanted to be stopped. Ever look at the various forums and see all the complaints about 'beLIEal more like beFAILal amirite?? lol y is azodon tellin me where he attack??? teh gaem say he the gr8est general. y iz diab0 tellin me bout his hell gaets????' They were leading you along to do exactly what they wanted you to do.

Sidebar: The Prime Evil, supposedly Diablo in the game. The following is said by Tyrael while on the quest, Prime Evil.

Player:
What do you speak of when you say the Prime Evil?
Tyrael:
It is the sum total of all seven Evils housed within one body. There is an ancient legend, known only to a few, of the great Dragon, Tathamet, who was the original embodiment of evil.
The legend says that he was ripped apart during an epic battle with Anu, and that the Burning Hells are composed of his remains.
Player:
Who is Anu?
Tyrael:
Just as Tathamet was the ultimate evil, Anu was the ultimate good. It is said by some that the Crystal Arch is all that remains of this great warrior.
Player:
Then Diablo seeks to become the Dragon once again?
Tyrael:
In a manner of speaking, yes.

So, either one Nephalem can be more powerful than what is basically one of the (accidental) creator gods of the entire universe, or Diablo was merely supercharged with the souls of the other Evils, and not really the Prime Evil, which even the CE artbook shows as a hydra thing. (Coincidence, D3 was codenamed Project Hydra?)

Also said by Tyrael:

But the Black Soulstone is flawed and cannot contain that many demons for long. We must capture Azmodan within it and shatter it... lest all these Evils be reborn.

Obviously that didn't happen because for reasons we will likely only know in the expansion, Diablo's body was just tossed over the side of Heaven, and the Black Soulstone was left intact.

Now, I don't know if it means anything, but it's near the end of the artbook. They're either concept art for the Child Emperor, or possibly for the future plot. Right below what looks to be a Cultist drawing, there are 3 children sitting 'Indian style' with elaborate headdresses. The middle one has a mostly different clothing style than the other two, while the other two are almost identical to each other. They both have 'face paint' or tattoos in red and blue on their face and bare chests, their eyes are shut with the 'paint' filling in their eyelids, and have what looks to be a 'third eye' possibly tattooed on their forehead. They also have some black jewelry on around their neck, upper left arm, and wrists.

"There is much about the future we cannot see, but when it comes it will be the children who wield it." - Adria, Diablo, talking about Wirt

So, we know if the BS isn't destroyed, the evils will get loose. The Nephalem are super powerful. Diablo possibly wants to re-make the Tathamet hydra. Theory: the Evils will possess children that Adria and/or Triune cultists have been raising after the Worldstone was destroyed, giving them massive power. Enough power to reform into Tathamet and smash the Heavens once and for all. (We, of course, thwart this plan by rescuing Princess Leah (has to be a reason they retconned Warrior into Prince Aidan) and find out her family's destiny is to bring back Anu and/or defeat Tathamet, which is why Diablo and the Evils were working to corrupt and destroy the Leoric bloodline)

Update: Some support for Princess Leah/Leoric bloodline's greater purpose?

So as we know, Mephisto was soulstone'd under the Zakarum Temple of the Light and was eventually able to corrupt them. What did those manipulated leaders do? Proclaimed Leoric king of Khanduras. The Archbishop Lazarus (bastard led us into a trap!) was 'intent' on Leoric choosing the 'broken-down monastery' as his seat of power. (Hmm, wonder why.. )

http://d3db.com/lore/i/leorics-journal-part-1

We have just arrived in Tristram, and I must say I'm a bit dismayed. This place is a backwater filled with serfs and an ancient, broken-down monastery, hardly fit for the king of Khanduras! I cannot fathom why Lazarus was so intent on this becoming our new seat of power.

http://d3db.com/lore/i/the-skeleton-king

The Zakarum high priests in Kurast proclaimed Leoric king of Khanduras many years ago. He ruled well until Diablo's influence drove him mad, and the loyal knight Lachdanan was forced to slay him. Afterward, Diablo himself raised Leoric from the dead as the Skeleton King until the monarch's son Aidan vanquished him.

However, the Diablo 1 lore almost seems to imply that Lazarus wasn't under demonic control until they had 'settled' and Diablo used his powers to coerce and eventually corrupt him.

Sensing that freedom was within his grasp, Diablo entered the nightmares of the Archbishop and lured him into the dark, subterranean labyrinth. In his terror, Lazarus raced throughout the abandoned hallways until he at last came to the chamber of the burning Soulstone. No longer in command of his body or spirit, he raised the stone above his head and uttered words long forgotten in the realm of mortals. His will destroyed, Lazarus shattered the Soulstone upon the ground.
...
Lazarus too, had fallen under the sway of the Demon, keeping close to Leoric at all times.

He also was apparently "a guardian of Mephisto's soulstone in Kurast" so it's up in the air, but I think he wasn't, as far as D1 is concerned, corrupted until they got to Tristram and Diablo reawakened, while in Diablo 3 he likely was corrupted from the get-go.

The wording is kind of vague, for what we are talking about here, but this piece also sounds like Leoric just came in on his own volition in D1 and was all 'For the glory of the Light! I am your king! I shall save you from the ever encroaching darkness! I claim this ancient Monastery as my seat of power in the name of the Zakarum!'

It was then that the great northern lord Leoric came unto the lands of Khanduras and, in the name of Zakarum, declared himself King. Leoric was a deeply religious man and had brought many Knights and Priests with him that comprised his Order of the Light. Leoric and his trusted advisor, the Arch Bishop Lazarus, made their way to the city of Tristram. Leoric appropriated the ancient, decrepit Monastery on the outskirts of the town for his seat of power and renovated it to match its time-lost glory.

It could just as easily be interpreted as what we know from the D3 lore, (although it has been retcon'd that he is an eastern lord now) that the corrupted High Priests told him 'Go be king here, in the name of Zakarum' and Lazarus was all 'Hey look, this building looks cool, right? What do you mean it's a dump? Castles are like so last year, you should just pick this place, I mean, we're already here, no?'

Personally, I'm thinking it was some minor retcons to go along with their current plotline, if solely for the fact that they felt the need to give the Warrior a backstory as a son to King Leoric of all things. For all that we saw of it in the game, the Warrior might as well have been just some nameless Warrior or Gheed's brother, as from what I remember, the whole 'Oh my Heavens, Leah is actually the heir to the throne!' plot hasn't come into play....yet.

Possibly going along with the whole 'The Evils were/are playing you like a fiddle' theory, Jay Wilson in some 2011 interviews (although he's talking about Diablo 2's perspective of course):

If the player thinks they outsmarted the forces of Hell and evil and they basically won, well, they are in for a big shock. Because what they are going to discover in Diablo 3 is that things have gone pretty exactly the way Hell wanted them to go all along.

What we really wanted was the idea of a story where we do have some time away, it’s about 20 years later, and things have actually gotten better because evil’s been “destroyed”. But the truth is that it’s actually all just been a ruse, it’s all part of the plan. It’s really just making sure everyone’s nice and complacent for the real war that’s coming.

From what I noticed in-game and from some out of game sources, if they are going to only have two expansions:

X1 - Save the Princess!
New classes: Templar Knight and Necromancer? Druid? (Templar Knight uses angelic runeblades/angelic spears and perhaps is like Paladin mixed with Javazon with some angel-ish powers. Necro is of course our old Necro with some improvements and refinements, same with Druid.)

Starts in Kingsport/Westmarch. You arrive on a ship or however, Kormac runs off on his own to challenge his Templars, Eireena possibly goes after him. You end up in a big battle with the Thieves' Guild. Finish that up, pay off the Merchant Guild, free his brother, pursue Kormac.

Battle your way into the Templar stronghold, demand answers. Reveal who and for what reason the Templars were given plans for angelic weaponry and set up to fight off an angel invasion.

King of Westmarch is revealed to be under demonic influence, hence his not sending reinforcements to battle an 'imaginary' enemy in Act III. Demon turns out to be one of Azmodan's Sin Lieutenants, new motive to destroy them all. Greed, Envy, Wrath, Pride, and Sloth remain to be seen.

At some point Leah plotline brought back into play. Seek out Cult of Rathma for assistance saving her. Journeying through the "Unformed Land" results in a history of the Leoric bloodline, revealing why that one family in particular seems to have such an affinity to Diablo. Lachdanan's spirit aids you in order to help Leah, fulfilling his promise to 'repay the (D1 hero) from beyond the grave if he could,' from a certain point of view. Spirits of the Warrior, Rogue, and Sorceror, perhaps, help you defeat some kind of boss in here. Lazarus?

Leah finally saved, brought back. Has a 'Uncle Deckard! I now know what you meant!' moment regarding her greater purpose. Adria has of course recovered the Black Soulstone, fight her and claim it. At some point Tyrael is killed, soul stored in the BS, leading to..

X2 - The End of Days

New classes: Assassin, Vizjerei, 'Dark Wanderer' (Assassin is of course based on D2 assassin with some tweaks, Vizjerei is more focused on elemental magic compared to the wizard's arcane, and 'Dark Wanderer' is a demonic power user)

…And, at the End of Days, Wisdom shall be lost
as Justice falls upon the world of men.
Valor shall turn to Wrath-
and all Hope will be swallowed by Despair.
Death, at last, shall spread its wings over all-
as Fate lies shattered forever.

So, either this prophecy occurred in the game and we take it at face value, that yes Malthael is gone, Tyrael fell, Imperius is mad as, no pun intended, hell, Auriel was attacked by Rakanoth, Lord of Despair, Diablo/the battles resulted in a lot of deaths, and the pre-determined fate that the angels would lose was shattered by the Nephalem hero.

Or, we may have only been led to believe these events occurred, and it was all a set-up for the future story. Tyrael the mortal abandoned Justice (claiming it had been met that day, despite himself saying only by destroying the Soulstone would the evils be destroyed) and took up Wisdom.
Hmm, a mortal is now Wisdom, which is going to be 'lost' when this whole prophecy kicks in, and Justice may 'fall' upon the world of men, meaning the Nephalem have to mete out future Justice since there isn't an Aspect of it at the moment.
Valor goes Wrath mode and wants to destroy the nephalem before they destroy the angels, especially since they were able to defeat the Prime Evil when he could not. Imperius' actions cause Auriel to lose hope, leading to despair. Archangel Malthael returns as the Aspect of Death and joins Imperius' crusade perhaps. Ithereal ends up 'shattered' and sent to their version of the Abyss for trying to stop Imperius.

Either way works I suppose for what might come next.

That prophecy is, according to Deckard Cain himself in-game, a warning about an 'ultimate invasion' of Sanctuary by the Hells.

The Prophecy of the End Days is contained within the Horadric tomes I inherited from my ancestor Jered Cain.
It is a warning to those who could interpret it regarding Hell's ultimate invasion of our world, written by many different people throughout history in many different lands.

Now, we know Diablo, Baal, and Mephisto all still had their armies since they were invading the Heavens. As far as I can recall, we only fought Belial and Azmodan's forces in Sanctuary. So, either all these ancient prophets (and who/whatever was giving them this vision) didn't account for random Nephalem to completely stop this 'ultimate invasion,' or the invasion has yet to come.

So, if the second interpretation of the prophecy is true, that would leave a very fractured Angiris Council, the perfect time for an 'ultimate invasion' of Sanctuary by the Hells to corrupt and 'use them as weapons,' which Tyrael says in a dialogue was the demons' goal. Meanwhile, Imperius was also planning an invasion, and thus three forces meet on the fields of Sanctuary: angels, demons, and nephalem.

The Wrath animation has Deckard Cain talking about how he fears the angel-demon war will soon engulf Sanctuary. and that the 'wrath of angels' cannot be quenched.

You also have the Templar order having been established by someone/thing to fight off angels.

There was also that Book of Cain interview, where 'Angels in Diablo are as nice as angels in our world' got an immediate 'Nnooo.' answer. 'I am afraid of Imperius' was also answered with a 'yes'

The lore in the D2 manuals is mostly about a 'final battle between men and demons' occuring in the future.

And, perhaps one of the biggest things, the Black Soulstone specifically being mentioned that it can hold demons and angels.

I think there may be some more hints towards the 'ultimate showdown' on Sanctuary, but I don't remember them at the moment.

So, there's these huge invasions going down, the Prime Evils possess Nephalem in order to get enough powers to re-form the Tathamet dragon. In any case, somehow this thing comes back.(The CE artbook has some art of Tathamet and Anu, it's in the first area after the classes I think if you have it, the opposing page has some really weird things, too) Leah realizes her true purpose is to bring back Anu to fight the dragon, does so using black soulstone/witch powers/family legacy. Big final battle with Anu and Tathamet duking it out while you run around on Tath and fight the various heads, things go boom, stage set for Diablo 4/'Domain of Diablo'

Some other things that may play a part:

Covetous Shen's Dirgest gem: Very likely this is going to be involved in some form, possibly as a boss you get to fight, depending on what it really is.

Scoundrel Relic: Said to be about the size of a fist and scarlet, possibly the same thing as Shen's gem? Or the heart of someone/thing? Don't remember enough about it.

Lilith/Inarius: Big role in the creation of Sanctuary, seems like we should see more of them. The above Book of Cain interview confirms that Inarius is still in Hell prior to the events of D3 at least.

Druids: Their Diablo 2: LoD lore says: "They created a new culture and language, cutting themselves off from their Barbarian cousins and their ways, vowing not to return to the Steppes of Mt. Arreat until the time of the Uileloscadh Mór, the final battle between the men of the world and the demons of the Burning Hells.
They have done this because they believe themselves to be the world’s last line of defense when the time of the great conflict comes, a time they believe is at hand."

Diablo 2 Heroes: That above Book of Cain interview confirms to us that 'Not all of them' are alive. If this ultimate invasion goes down, you can bet they will be involved, either helping us or corrupted like the original Diablo heroes.

Those giant things in 'eternal torture' in Act III: These things are pretty messed up, they have their hands nailed to their shoulders etc. The following lore mentions Inarius' followers 'shar(ing) an even darker fate' (darker than death). Maybe this is mentioned in the books, but those giant things look like they have attachments for wings on their back, might the 'even darker fate' involve being trapped in some giant, eternally tortured, body?

UPDATE: Had an epiphany a bit ago, remember in D2 how Izual was, you guessed it, trapped in a demon's body? If these are what happened to those Inarius followers, well, there you go.
http://d3db.com/lore...anctuary-part-4

In the end, Lilith was banished and Inarius was given over to the demons, who have tortured him in the Hells ever since. Most of Inarius's followers were killed; those who remained shared an even darker fate. Despite the tragedy, I believe the nephalem may yet play a part in resolving the Eternal Conflict.

http://d3db.com/lore/i/colossal-golgor
Could this demon be Dirgest? Or is it something we already know about from the books or something.

The colossal golgor is merely a colossal myth! In folklore, they are sons of an infamous demon who smashed half of Hell in anger after the Prime Evils were defeated during the "Dark Exile." Why, if I had a gold coin for each of these tales, I would be a wealthy man indeed!

http://d3db.com/lore/i/grotesque

The grotesques may seem slow and senseless, but they hide many dangers within their hideously malformed bodies. A set of spikes lurks beneath the monsters' flesh, and foul parasites nest within them. It is said that these horrors themselves are constructed by a greater evil... a darkness that I cannot even fathom.

http://d3db.com/lore...he-mallet-lords

The mallet lords are brutal overseers second only to the seven Evils themselves. The mallet demons rule the seething outer reaches of the Hells that surround the central realms, and have long refused to join any of the Lesser Evils' armies. Surely the destruction would be unthinkable if such a thing ever came to pass.

Quote from Amphetamine

So we finally have the complete list of bosses:

Act I
Skeleton King
The Butcher

Act II
Maghda
Zoltun Kulle
Belial

Act III
Ghom
Siegebreaker Assault Beast
Cydaea
Azmodan

Act IV
Rakanoth
Diablo

:/ I was hoping for Imperius!

Might be out there in other locations already, but had a GameFAQs topic open while browsing this one, and someone claiming to have the guide posted this as the full boss list for Act I and II. HUGE SPOILERS, of course.