Part of the problem with World of Warcraft is the game has a lot of ground to cover — an entire world, in fact. Players also pick everything up and shuttle off to a new continent with every expansion. The main continents in World of Warcraft haven’t been updated since Cataclysm. It’s another team, in another Blizzard game, that returns to these playgrounds and spruces them up, turning them into little worlds of their own.

Now, Blizzard’s digital card game Hearthstone is bringing a long-running, over-the-top story campaign to the Cataclysm zone of Uldum.

Uldum is one of most fascinating zones in World of Warcraft, and in the MMO, we only scratched the surface. Now, we’re getting a proper deep dive.

Hearthstone house rules

Hearthstone isn’t quite proper canon, even though the game and World of Warcraft have a lot of overlap. Characters, scenarios, and locations cross back and forth between the two games, but the two maintain separate canons. For instance, in World of Warcraft, Gadgetzan is a small goblin city. In Hearthstone, it’s a thriving, bustling port. Battle for Azeroth’s Tortollans started in Hearthstone, then migrated over.

Oh, and in World of Warcraft, the flying city of Dalaran waits over the Broken Isles. In Hearthstone, a collection of criminals and villains strapped mega rockets to the city so they could steal everything in it, and also the city itself, and are using it as a mobile headquarters.

The League of EVIL is now heading to Uldum, where the Explorer’s League will have to stop digging and stop the whole thing from snowballing further.

“We always wanted to have a big, epic jaunt with all of our villains and heroes together,” said Dave Kosak, lead designer for missions on Hearthstone, in an interview with Polygon. “If you want to do a one-year story, you might as well make it big, epic, and sweeping and go all over the world. But a risk of doing a yearlong story is, what happens if people aren’t into the theme? Do they just not play Hearthstone for a full year? That seemed kind of bad.”

Hence, smaller themes: a criminal heist in Dalaran that naturally leads to an adventure in the Uldum deserts. Uldum makes for a great setting. First of all, the team wanted to bring out the League of Explorers, who have been established in previous Hearthstone expansions. Secondly, Uldum is packed full of potential: ancient Titan temples and old, forgotten ruins. There’s also a big, wide desert, which offered a fun ecology to experiment with. There’s an Indiana Jones-style whimsy to it all.

Exploring Uldum

A wide and varied cast of over-the-top archetypes also allows Hearthstone’s quest designers to come up with new hero powers, win conditions, and boss encounters. “[Uldum] gives us a lot of story to hang our hat on, but it also implies a lot of mechanics that we wanted to do, that artists and designers could have fun with.”

“Our team is always digging into games, movies, all of that. We’re already nerding out on other people’s techniques and how they pulled off a specific cool effect or something like that,” said Hadidjah Chamberlin, lead FX artist.

Because World of Warcraft mixes so many influences together, that means special effects and scenarios can go outside the realm of strict fantasy and into other genres. But when World of Warcraft moves on from a zone, players don’t return. Hearthstone is able to go back to these environments and dial the elements of them up to 11.

In World of Warcraft, Uldum is a buffet of unexplored, but cool, concepts. It juggles a political story between ancient races of feline guardians left to protect god-constructed technology, excavation groups from around the world coming to explore these new wonders, and powerful elementals staking a claim for their nefarious Old God masters. All of these concepts were only half-explored, largely linked together by pop culture references.

As Blizzard expands Hearthstone’s single-player campaigns and adds more boss fights, it’s able to dig deep into corners of the world that the MMO simply can’t go.

Honing the craft

The Hearthstone team has been paying increasing attention to its single-player campaigns, which are proving to be one of the best parts of modern Hearthstone.

“We learned a lot from our very first take on this mode [in Kobolds & Catacombs],” said Kosak. “What we discovered is that the boss doesn’t have to be too complicated, because the real fun is in building a deck. So we just started approaching a boss’ design as like, let’s just make sure this character is fun and they do something interesting to challenge you in a unique way.

“We can break a lot of rules. You can be mean to the AI, and we don’t care. We just have to be careful that you break the rules in ways that are meaningful and fun, which is tricky, but it’s a lot of fun to explore.”

There’s rarely a major stumble for the developer when it comes to implementing these bosses, although sometimes the team overshoots.

“Sometimes we design a boss, and we’re like ‘holy cow, this boss is impossible, let’s tone him down’,” Kosak said.

Kosak couldn’t think of an instance where the team ever went too far in designing a core mechanic for a boss — tweaks are often just to numbers, not complete reworks. One change that was met with suspicion is the ability to enter non-combat encounters on the Hearthstone board to switch up a deck.

The goal with these encounters was to avoid UI-driven menus that pull players out of the game.

“We want you to have this feeling where you come into an environment, and there are these characters milling around and you can recruit them,” Kosak said.

Players are likely going to see Uldum expand, much like how Gadgetzan is now a thriving, noir-esque port town and Area 52 is home to Dr. Boom and his puzzle labs.

“When I found out we were doing Uldum, I was like... oh my god, it’s a giant freaking desert. It’s going to be nothing but sand everywhere. It’s going to be the best,” said Chamberlin. “The amount of variety there is cool, and that comes across in these different mechanics and in the art we use across the board. There’s such a trove of stuff there already, and it’s really fun. I work with that, and spin it out in wild directions.”