Unmodded and running at 800 x 600 resolution, Diablo II: Lord of Destruction is still my favorite action role-playing game. I've tried many other Diablo-style games since, from Titan Quest to Dungeon Siege to Torchlight (made by several of Diablo's creators) to Baldur's Gate: Dark Alliance, some of which improved on Blizzard's design with less restrictive skill systems, better interfaces, more advanced visuals and added conveniences for travel, item storage and looting. But I've never played one and thought, without a doubt, that as a whole it established a higher standard than what Blizzard North achieved in the very early 2000s.

A lot of that has to do with gameplay, but what still stands out in Diablo II is the mood. The soundtrack in particular, its cascades of reverberating guitar, pounding drums and heavy, sawing strings lends Diablo II its unsettling atmosphere to a greater degree than any other aspect of the game. It's a tone of piercing loneliness, of mounting terror as you proceed step by step, map by map through increasingly bizarre, twisted and violent realms, fighting bigger, nastier enemies armed with devastating ways to kill you.It really shouldn't be a scary experience. Diablo strikes an unlikely blend of horror and comedy. You'll routinely come across dead bodies lying around Diablo II's environments that very clearly show this is a terrible place populated by even more terrible creatures. Then when you click to loot the body, a giant magical halberd pops out accompanied by a sound effect like a cartoon character doing a backflip.We accept this as an integral quality of the game world. Of course health potions are dropped from butchered quill fiends, we need them to survive. Of course spectral, mana-leeching winged demons drop gold, we need it to gamble at the town vendor. The acceptance and dismissal of Diablo's built-in goofiness that should, at least theoretically, undercut all sense of terror generated by the sight of Hell's armies, happens almost instantly. Click, kill, collect becomes as natural as the notion that humans have five fingers.From there, it's easy to get swept away by the sense of progression Diablo II fosters, achieved by still impressive environment and monster design, a huge loot table and an ever-present feeling of vulnerability. No matter how sturdy your heavily-armored character may seem, it only takes one pack of lightning beetles or a breath of fire from a fetish shaman to kill you. The threat of a monster swarm erupting from the darkness around you keeps your eyes glued to the sides of the screen. What is that shifting silhouette beyond that stone gate? A small pack of zombies? An army of skeleton archers backed by the resurrecting power of greater mummies? Such moments of anxious anticipation are near constant in Diablo, but there's no reward in turning away. If you see the glow of a champion monster behind a closed door, opening it is near irresistible because, by that point, you're conditioned to know a bigger challenge means a greater reward.This sense of vulnerability is tied to one of Diablo II's relative weaknesses: the potion system. No matter your skill build, no matter your armor set, don't expect to survive for long without a belt full of healing potions. In some cases, such as in the face of a mob of knife-wielding fetishes, there's really no way to win by standing still and fighting as you normally would. Retreat and hair-trigger potion use becomes essential. Yet as much as this type of unbalanced system encourages exploitative behavior – funneling charging enemies onto a narrow bridge to fight them one at a time, retreating behind a doorway and waiting for your hired mercenary to soften up the pack, opening a town portal and simply leaving – without such high risk, the play experience wouldn't be as exciting.I suppose for someone who thrives on true risk, the hardcore permadeath mode is the way to play, but that's never been especially appealing to me. I don't want recovery from a mistake to actually be impossible, just momentarily seem that way. At creating that impression, Diablo II is better than any other action-RPG I've played. No game so fluidly and rapidly alternates between a sense of relative safety and full-on scream-at-your-monitor pandemonium. As much as the potion system balancing results in difficulty spikes so high there's little alternative but to run, the ever-present threat makes sense considering you're fighting the forces of Hell.In cases where you can stand and fight with the skills you've carefully activated and upgraded while leveling, no game since provides the sense of satisfaction I get from utterly mauling a pack of enemies. Gory fireworks explode with nearly every kill as each monster type exhibits a different death animation. Fallen spin to the ground and squeal as they spit out a semicircle of blood, giving the thump of your weapon's killing strike a sense of weight. This all happens in under a second and is repeated ten, twenty, thirty times per monster group as loot explodes alongside bodies, monsters and mercenaries cast spells and you make efficient use of your equipped skills.Not only does wholesale slaughter award experience, it provides a constant stream of rewards. Every time you click to attack, you pull a slot machine arm. The draw of the loot system isn't simply netting an item with +5 dexterity instead of +3, though that's part of it. It's all the ancillary effects: the percent chance to cast a frost nova when hit, the increased gold percentage find, the extra fire damage, the increased chance to block. It's a feverish race to acquire that perfect set of gear that you're constantly assembling but seemingly never able to complete.Naturally, the better items are rarer. Coloring item names in accordance with rarity is common in video games, something Diablo popularized. The first time a yellow item drops is like an extra present at Christmas. All you can see is its name, teasing you with hidden potential. Unwrapping it is a simple matter of picking it up and activating a scroll, and with each step you savor the possibilities, imagining your ideal statistical bonuses. Finally you click to unwrap the item and a wall of magic effects explodes across the description pane. Your eyes frantically scan the page to see if the real stats match those you imagined. Half-freeze duration is stacked with poison resist and enhanced defense and a minor bonus to light rating, and suddenly the gloves you'd been wearing, which only a short while ago were your best item, seem like trash. You swap, and sprint into the field more confident than ever.Gradually the names of all the items equipped are gold and yellow and green and the item description text fields take up nearly half the screen. Your equip menu is a trophy rack, a perpetually shifting collection of valuables that appeal to your vanity as much as enhance your survivability in the field. Though this concept is hardly unique to Diablo, few games at least in the action-RPG space, have managed to build a loot system that compares in terms of depth and variety. Because loot is randomized, getting anything that perfectly suits your skill build makes you feel like a lottery winner, and the chance it could happen legitimizes continued searching.And Diablo II gives you the chance to continue, over and over, recycling its own content tuned to higher difficulties. The whole time its tone of encroaching dread, from the stony fields surrounding the opening rogue encampment to the chambers of Diablo's most merciless creatures, never lightens up. There's a pervasive sense that you're venturing into eldritch, forbidden spaces; that you're forced by weak-willed villagers too timid to venture beyond the walls of their homes into spaces no rational creature was ever meant to see. That alone makes adventuring exhilarating, amplified by the shadow-soaked visuals and outstanding dungeon and monster art.Sure it can turn into a grind eventually, everything does, but no grind in virtual or real worlds offers so many types of rewards so quickly, and makes acquiring them so satisfying. Diablo II is a big game stuffed with content, yet its pace of progression never lets up; even the health potions evolve in restorative power and icon design. Many great action-RPGs followed Diablo II, but none have managed to generate the thrill of battle and sheer euphoria of success as effectively Blizzard North's gothic epic. Maybe after Diablo III and Torchlight II launch in 2012, that will change.