How 'Diablo' Defined the Hack 'n' Slash Role-Playing Game

Blizzard's hellish dungeon crawler turns 20 this month. Here's why it mattered.

1996 PC dungeon crawler, 'Diablo', turns 20 years old this month. Credit: Glixel

Until the 1990s, roleplaying games were often intimidating, aimed at an audience already familiar with Dungeons & Dragons and The Lord of the Rings. There was a lot of reading involved – games like 1988's Pool of Radiance were accompanied by a manual full of numbered paragraphs of text you'd be directed to read at various points to find out what was happening. There was also a ton of math, with arcane systems determining how many hit points characters received or the maximum level various race and class combos could achieve. RPGs were for the serious students of the video game classroom, the ones who sat at the front and paid attention.

But then, at the very end of 1996, Diablo came along. After popularizing fast-paced real-time strategy with Warcraft two years earlier, Blizzard were ready to repeat the trick with an RPG that ran at a similarly frenzied pace, and did not sit anywhere near the front of the class. Diablo sat at the back and drew skulls on its Trapper Keeper.

It didn't start out that way. When David Brevik and the other designers at Condor (later Blizzard North) first dreamt it up, Diablo was another turn-based game about controlling a whole party of characters. Only as it evolved did it become faster, easier to pick up and play. Looking at the original pitch document, you can see Diablo was going to have “many races and classes”, but by the time of release they'd been rationalized down to just three regular humans – the warrior, rogue, and sorcerer. Character creation went from a 20-minute prologue before the game even started to a single decision: pick one and let's go.

Every aspect of Diablo was as lean as its character creation. Combat was reduced to clicking on enemies till they died, with the occasional keypress to drink a potion or swap which spell was tied to your right-click. Leveling up was a straightforward choice of where to spend a handful of attribute points, and loot was as plentiful as it was nonsensical. Kill an archer and they might drop an axe, kill an axe-wielder and they drop a sword – entirely random gear and coins showering out like popped pinatas.

Its simplicity made Diablo compulsive in a way most RPG players weren't used to. My first introduction to it came at a LAN party, where we'd normally bounce from one game to another. After a round of Age of Empires we'd play Grand Theft Auto or Total Annihilation, but when we tried Diablo something different happened. One of the players didn't want to stop and bounce on to the next game – he spent the rest of the afternoon leveling up his warrior alone, unwilling to tear himself from the loop once he was in.

The fantasy setting of Sanctuary may be a nice place for us to visit, but it would be pretty rough to actually live there. Corpses crawl out of their graves, Hell sends demons to invade while Heaven remains aloof, and Cain the Elder – Diablo's answer to Gandalf – drones interminably at anyone in earshot. The village of Tristram teeters on the edge of doom every five minutes, whether from the red glow of the cursed cathedral or wyrms boiling up through someone's basement. It's a blood-drenched grimness that's immediately appealing to teenagers whose favorite adjective is “dark” – the rejection of Tolkienesque tropes seems like another act of teenage rebelliousness, and the game's ending feels designed to impress them with its edginess – and that's where Diablo found its most receptive audience.

It's not all serious business, however. The sidequests form a goofy contrast, like the storyline in which monsters steal Tristram's tavern sign and then fight over it, chunky overlords on one side and blue imps led by a chief named Snotspill on the other. The silliness lightens the mood so that it never becomes too oppressive, and nasty as Tristram would be for the inhabitants it's always a blast for players to return to.

It's worth returning to again and again thanks to procedurally generated dungeon levels that are never the same twice, even if the click-to-kill combat you perform in them is pretty samey. Random dungeons are something Diablo inherited from the permadeath games in the “roguelike” genre like 1992's Nethack or the 1990 Tolkein-inspired Angband that make up part of its DNA – and remain there thanks to hardcore mode – but Diablo also built on preceding “action RPG” games as well, like the arcade stylings of Gauntlet.

The action-RPG wouldn't be the same after Diablo. Games like The Legend of Zelda that were once considered part of the genre would be reclassified as “action adventure” while games with hotbars of items and abilities and highly visible health and mana bars flooded stores. Each of them tweaked the format slightly – Dungeon Siege made it even simpler, basically playing itself, while Revenant added carefully measured doses of complexity in the form of directional dodges and martial arts moves – but were close enough that the name “Diablo clone” was interchangeable with ARPG for years.

Even games in the more classic RPG style felt the pull of its changes. The original Fallout, then in development, was put under pressure to change from turn-based to real-time combat (and add multiplayer) in imitation of Diablo, as designer Tim Cain explained in his post-mortem years later, calling Diablo a “thorn in my side.” Other games like Baldur's Gate and Planescape: Torment were made given a compromise: real-time combat with the option to pause, and without them we wouldn't have Dragon Age or Pillars of Eternity today. Modern ARPGs like Path of Exile, Grim Dawn, and the Torchlight series continue building on its foundations, and of course Diablo had two sequels of its own.

The latest sequel, Diablo III – which launched in 2012 – is about to celebrate the birthday of its forebear by replicating the original within it. It’ll be interesting to compare the 20-year-old to its descendants. Though they made improvements in areas like multiplayer – online Diablo was infamous for its cheaters – the follow-ups never had quite the same clarity as the original. It may seem odd to praise the clarity of a game that limited your field of vision to a circle of light and had isometric walls that sometimes blocked your view almost completely, but Diablo was designed with its limitations in mind. Reducing the significance of sight made hearing important, and the sounds of its monsters and loot remain instantly recognizable. The braying goat demons of the Flesh Clan, the chittering of the Fallen, and the clatter of bones as a skeleton collapses – as well as the hollow clonk of a falling helmet or the delightful ching as coins tumble in a pile – all are deliberately distinct. They helped give Diablo an atmosphere of its own, one that none of its clones or sequels ever bettered.