Looking forward to Diablo III, but haven't played it in ages and can't remember the story? Don’t know the difference between a Soulstone and a Worldstone? No worries – we’re here to help. Here’s all the info you’ll need to jump into Diablo III with the knowledge of what’s going on, who you’re fighting, and what you’re fighting for. Once you've brushed up on the lore, be sure to check out our Diablo III review to see what else awaits you in the highly anticipated sequel.

Before humans, there were only angels and demons - and they hated each other quite a bit. As it turns out, the forces of order don’t take too kindly to the armies of chaos, and their evenly-matched warfare became known as The Great Conflict. It was these battles that forged warriors like the archangel champion Tyrael and spawned the grotesque legions that follow the Prime Evils. We never get to see any remnants of The Great Conflict, seeing as those wars took place eons before the events of the original Diablo, but we do get to meet some of its greatest generals – and kill them.

Never-ending war between Heaven and Hell is… hell, and it can wear at even the noblest figures. Inarius, an angel on the same Angiris Council as Tyrael, got tired of it all, and decided to go into exile from Heaven to create his own domain. With the help of other defectors, including Mephisto’s demonic daughter Lilith, Inarius took control over the Worldstone, a powerful crystal housed in the Pandemonium Fortress (which you fight through in Diablo II’s expansion, Lord of Destruction). Using their combined powers, Inarius and his posse managed quite the godly feat: creating Sanctuary, the first corporeal world outside of Heaven and Hell, and giving birth to the Nephalem, Sanctuary’s first human inhabitants.

Inarius hid Sanctuary within the Worldstone to hide it from the forces of Hell and Heaven, but conflict between Inarius and his followers eventually brought its existence to the attention of Tyrael and the forces of light. Instead of viewing the Nephalem and their descendants as a species to be nurtured, the angels were repulsed by these unknown lifeforms. Tyrael’s first instinct was to wipe the humans out – but after observing their aspiration and will to live, the humans started to grow on the big angelic guy. He became a true ally to the people of Sanctuary, and helped us out countless times through the events of Diablo II.

Sanctuary was supposed to be neutral territory, but the demonic forces of the underworld had different plans. Hell houses seven Great Evils in total: three we’ll get to in a second, and four Lesser Evils. You’ve got Belial, the Lord of Lies; Azmodan, the Lord of Sin; Andariel, the Maiden of Anguish; and Duriel, the Lord of Pain (the latter two are the bosses of Acts I and II in D2, respectively). They weren’t too pleased with taking orders from their more powerful masters, so they plotted to overthrow them – and after a bloody battle, they succeeded. Azmodan and Belial bickered over who would control the remainders of Hell; it’s likely that we’ll fight them in Diablo III.

Banished by the Lesser Evils to exile in Sanctuary, the three Prime Evils are the guys you never, ever want to see in your hood. There’s Mephisto, the Lord of Hatred; Diablo, the Lord of Terror; and Baal, the Lord of Destruction (hence the D2 expansion’s title). These three demonic brothers command vast power, and on the plane of Sanctuary, they were without equal. Mephisto is the wily strategist of the bunch, Diablo prefers brute force, and Baal uses power in numbers. Their arrival is still pre-Diablo 1, but there would be heroes who would challenge their hellish might.

Recognizing the threat that the Prime Evils posed to the innocent inhabitants of Sanctuary, he assembled a Power Rangers-like super squad of the most powerful mages he could find. Among their ranks was Deckard Cain’s great ancestor Jered, and they were led by Tal Rasha (whose tomb you explore in D2’s Act II). Their task: hunt down the three Prime brothers and trap them so their reign of terror would end. But how were they supposed to defeat such fearsome creatures as the Prime Evils? Simple: by using soulstones.

Knowing that the demons couldn’t be destroyed through conventional means, Tyrael provided his hand-picked team of magi, which he dubbed the Horadrim, with three soulstones. These inconspicuous-looking crystals had the power to imprison the essence of each demon, so they would be sealed away forever. The Horadrim succeeded in tracking down and confining each Prime Evil within a soulstone – now the problem was finding a place to put them where they could never be disturbed.

Baal’s soulstone was fractured during his takedown, so Tal Rasha volunteered to plunge the stone into his chest; acting as a human prison, he was buried deep within an ancient tomb. Mephisto’s soulstone was put under the care of a group of monks, and Diablo’s stone lay dormant under a cathedral that the Horadrim built to hide its location.

Trouble is, the soulstones aren’t 100% airtight demon-traps. The three Prime Evils’ influence could still be felt in the vicinity of the stones’ locations, and they could manipulate and persuade unsuspecting humans to do their bidding. Mephisto was guarded by the Zakarum monks of Kurast – but judging from their mutated appearances and hostile tendencies in D2’s Act III, he corrupted their minds without much trouble. Baal’s presence drew Tal Rasha insane, and as Tal Rasha’s body withered away in the tomb, Baal began to regain power. Diablo’s soulstone still remain untouched under the Horadrim’s cathedral, but as time passed, people forgot the structure’s original purpose. Tristram was founded around the cathedral, kicking off the events of Diablo 1…

King Leoric ruled over the land of Khanduras, a kingdom with Tristram as its capital. With the aid of his right-hand man and advisor, Archbishop Lazarus, Leoric established his throne in the now-abandoned cathedral the Horadrim had erected, unknowingly establishing a conduit for the Lord of Terror’s evil energies. Though he was unable to possess King Leoric directly, Diablo used his unseen influence to warp the mind of Archbishop Lazarus, coercing him into kidnapping Leoric’s son to act as a host.

The hero of Diablo 1 ventured into the depths of the cathedral to slay Diablo (canonically, Leoric’s warrior son Aidan was the one to defeat the big red guy). But even after being trapped in the soulstone once more, Diablo was able to corrupt the hero’s mind, convincing him to plunge the soulstone directly into his forehead. Instead of banishing Diablo back to the void of the soulstone, the hero ended up giving him an even stronger body to possess.

This poor sap got caught in a battle between worlds, when all he wanted to do was smoke his pipe. Marius was relaxing in the same tavern as Diablo 1’s hero (now referred to as the Wanderer) when the Wanderer had a bit of a demonic-possession episode, killing everyone around him save Marius. Stunned at the catastrophe around him, Marius becomes further and further unhinged, which isn’t helped by the fact that the Wanderer beckons to join him on his journey. Over the course of Diablo II, an increasingly-insane Marius obeys the orders from Diablo and Tyrael alike - but he dooms humanity when he mistakenly relinquishes Baal’s soulstone to the Prime Evil himself, thinking him to be Tyrael. Mephisto and Diablo may have been slain and their soulstones destroyed, but that still left one loose end.

Now in possession of the one object that could defeat him, Baal turned his sights to the Worldstone, the source of Sanctuary’s protection and a gateway to other realms. It remained hidden in the mountains of Mount Arreat, where barbarian settlers had made a home for themselves called Harrogath. Baal sieged the small city with a massive army, but the heroes of D2’s expansion were able to push them back and track down Baal. Unfortunately, Baal managed to corrupt the Worldstone before his death, and drastic measures had to be taken…

Taking matters into his own hands, Tyrael made the critical decision to nip the pressing problem in the bud. Warping to the Worldstone Keep after Baal falls, he transports the party of heroes back to Harrogath in preparation to enact some angelic demolition. Knowing that the Worldstone’s been tainted beyond repair, and could threaten all life in Sanctuary, Tyrael heaves his sword of light into the crystal, shattering it into thousands of pieces. That was 20 years before the events of Diablo III, and nobody’s heard from Tyrael since.

Having studied the heroics of his magi ancestors, Deckard Cain is an expert on all things related to the Horadrim, including D2’s Horadric Cube. This frail old historian winds up in the most unlikely of place – he’s there to help in Diablos I, II, and III, whether via giving quests, identifying items, or acting as an interpreter for Tyrael’s vague commands. Also, he sounds a little bit like an elderly Sean Connery. He’ll play a key role in Diablo III, as his adopted daughter Leah seems to be getting quite a few demonic visions lately…

Leah takes after her Uncle Deckard, studying the relics of the Horadrim and researching the humans vs. demons battles of past generations. Knowing that the Lesser Evils Azmodan and Belial are still waging war in Hell, she seeks to imprison them using a fourth soulstone she’s recovered: the Black Soulstone. (Diablo’s was red, Mephisto’s was blue, and Baal’s was yellow, in case you were wondering). But recovering the artifact has alerted Azmodan to its presence, and he seeks to hunt Leah down and destroy the Black Soulstone before it can be used against him. There’s no doubt in our minds that Azmodan and Belial will have a bone to pick with our Diablo III character…

While that Diablo plot recap should get you ready for Diablo III, there’s plenty more details to fill in the gaps between games, as well as standalone novels and supplemental books (we highly recommend the Book of Cain). If Blizzard’s excellent lore sounds like something you could sink your teeth into, check ‘em out!

Hop over to our Diablo III review to get our final verdict on the long-awaited game. Need to get up to speed in other games? Check out the 21 must-know facts about the Mass Effect universe to get the skinny on Commander Shepard’s storied military career, or get even more hyped for Diablo's return with our 13 reasons to get excited for Diablo III.