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Over 3000 kills, more than 200 hours, and only three bosses to grind. For over 22 years, this was the tedious routine of the average level 98 Diablo II player—all to gain a single level.

With the advent of its second season in September of 2022, Diablo II: Resurrected underwent a metamorphosis. For the first time in decades, new major features debuted: Terror Zones, intended to help players level up in more diverse ways, and Sundering Charms, which enabled characters of any class or build to break monster immunities.

The story behind the creation of these two features begins with an earnest desire: to make Resurrected more accessible, fun, and less of an unchanging grind for players. And two members of the Resurrected team—Senior Principal Game Designer Robert Gallerani and Software Engineer Michael Clavell—helped shepherd that wish from inception to realization.

Masters of the remaster

The shelves behind Gallerani brim with cartridges for a slew of different consoles, a personal library that spans generations of gaming history. He turns for a moment, sifting through a portion of his collection, before plucking an item and showing it to us: a copy of Tony Hawk’s Pro Skater 2, sealed inside a Game Boy Advance box.

It’s the title at the core of both his and Clavell’s resumes. The first game he ever shipped, Gallerani says, was the GBA port of Pro Skater 2; the first game Clavell shipped, over 20 years later, was a remaster of the PlayStation’s original Pro Skater 2. Now Gallerani, tied to the legacy of a decades-old game that would later receive a remaster, helps helm a similar endeavor for Blizzard.

A veteran of the industry, Gallerani graduated with a degree in animation over two decades ago and went on to lead design on a number of games at Vicarious Visions, the former iteration of the studio now known as Blizzard Albany. There, he was eventually joined by Clavell.

“I was most likely still learning to read while he was already working at VV,” says the much younger Clavell. “I graduated with a game design degree. Those probably didn’t exist back [when he was in college], either.”

After joining the team, Clavell began working on the in-development Resurrected—an undertaking that was, according to him, surreal. He’d grown up immersed in the gaming sphere, where he’d heard Diablo II touted as a mainstay of action role-playing games. “Then, all of a sudden, I’m working on its remaster,” he says. “Then, after that, we’re working on new features for it and fixing bugs that have haunted players for decades. It’s very exciting.”

Paving old potholes along the path to 99

Remastering any beloved game is a tricky process to navigate; remastering a game that’s old enough to apply for a credit card? It was “terrifying,” says Gallerani. “Diablo II was peoples’ childhoods. Adding to the game is a delicate balance, and we have to do it respectfully. But, on the other hand, we can’t have too many sacred cows, or else we’ll never be able to bring anything fresh to the table.”

When the team began ideating on Season Two’s potential new features, they first analyzed how players approached the storied race to level 99. Reaching that level cap is a prestigious achievement accomplished by only a fraction of Resurrected’s millions of players. In Season One, only 787 accomplished it in softcore mode, which allows one to respawn after death, and 136 in hardcore mode, where death is permanent and forces a player to start again from level one. For Gallerani, watching streamers compete to hit 99 in Season One made two things clear.

The first: Diablo games are all about efficiency, and the players chasing time-intensive achievements will always figure out the most cost-efficient method of doing so.

The second: The potential of Resurrected’s world, Sanctuary, was going untapped at the highest echelons of play. 

The reigning method of getting to the game’s highest level—killing the bosses Baal, Diablo, and Nihlathak ad nauseam—felt too restrictive and unimaginative. Grinding to 99 also often required players to utilize one of the few class builds capable of doing so efficiently, like a Necromancer wielding the Amplify Damage spell or a Paladin with Conviction aura.

“Even though there’s a lot of nostalgia associated with it, grinding one or two monsters over and over again without sleeping to make it to level 99 didn’t appear fun to us,” says Gallerani. “So, we wondered: How can we make the game more fun to play, more exciting to watch, and get more people into it?”

Once they had compiled their observations about Season One, the team started drafting designs for Season Two. And thus, fashioned upon the anvil of ingenuity and tempered in the broiling flames of the Burning Hells, two new features were forged.

Upping the infernal ante

The Resurrected team’s approach to designing Terror Zones and Sundering Charms was simple. “We’ve got a whole lot more game,” says Gallerani. “Is there a way we can make the rest of it as rewarding as those three bosses?”

The team tried several different methods, like allowing certain bosses to roam or having debuffs randomly appear on players. Ultimately, they went with the most straightforward idea: Just take the whole zone and jack it up.

Setting the level of an entire area to something absurdly high, Clavell says, sounds simple in concept but led to issues when executed. “Our first iteration didn’t scale with player level,” he recalls. “We just made the whole zone level 96. And during our playtest, we had feedback that was like, ‘What if I’m level 70 and still getting no experience?’”

That line of questioning led them to their current version of the feature, where the monsters in each zone will scale based on the player’s individual level and the level of difficulty they’re playing at. Once the team had solidified the concept of Terror Zones, though, they realized that amplifying certain regions of the game also amplified a pre-existing issue that Diablo II had never quite addressed: immunities.

The “immunities problem”

In Diablo II, monsters can be impervious to specific types of damage, regardless of how overpowered a player’s character is. Gallerani recalls that, “Now, since players could experience pretty much all of Resurrected at a very high level, it started to show off more of the game. And, yeah, immunities were always there, but now players had to deal with more of them.”

The “immunities problem,” he says, is what led to the creation of Sundering Charms alongside Terror Zones. Since the early days of Resurrected’s development, the team had been discussing how best to address immunities and the way they’re communicated in-game to players.

“It’s not as if, at level one, there’s a monster that goes, ‘I’m immune!’ and then it teaches you how to get around that,” says Gallerani. The game doesn’t concretely articulate anything about immunities to players until, for some, they might already have invested dozens of hours into a character and chosen abilities that suddenly become useless against certain enemies. “Then, it’s like—surprise! You can’t ever beat these monsters because we said so!”

To deal with this issue, the team settled on the concept of items that break specific monster immunities. These Sundering Charms improve class builds, but they come with a caveat—reducing a monster’s immunity will also reduce the player character’s own resistance to that same element. And just like everything Diablo, there are some good Sundering Charms, along with some...less good ones.

“The Sundering Charms that are less useful actually have a lower chance to drop, and the more useful ones have a higher chance,” Gallerani says. “You have to consider who we made these for. We didn't make them for the hardcore audience who know how to get the right Rune Words to break through these immunities—we made them to help more people start playing and make more builds viable”

Terror unleashed

After countless rounds of internal iteration, the team realized it was time to nudge their designs out of the frying pan and into the hellfire of the Public Test Realm [PTR], where players could experiment with the mechanics before their implementation into the actual game.

“We have an awesome [Quality Assurance] staff, and we think we know what we’re doing most of the time,” says Gallerani. “But having the community try it? There’s no faking those numbers. The only way to know what a million people think about your game is to let a million people play it.”

Once the content was released for testing, the community was enthusiastic to engage with it, booting up the game’s PTR on Battle.net to experiment and relay their feedback to the team. Now, some time out from the feature’s implementation, Gallerani and Clavell have enjoyed watching players devise new strategies, discuss formulas to math out the best ways to optimize leveling, and create online tools to keep track of each Terrorized zone.

But watching people fiddle with Season Two’s features has led to another revelation: If there’s a programming quirk that can be taken advantage of for the sake of entertainment, players will find it. Some of Resurrected’s most innovative adventurers, for instance, discovered that they can herd non-Terrorized monsters into a Terror Zone, portal back to town, wait a little while, and then portal back to find that monster now Terrorized.

"I was thinking about it from a programming standpoint, and...yeah, that's a bit weird and funky, but also...why would you ever do that?" says Clavell, laughing.

Anything to make leveling more fun, we suppose.

Venture into Sanctuary to brave the Burning Hells’ fiendish armies and try out Terror Zones and Sundering Charms in Season Three of Diablo II: Resurrected now.