Scant few games stand the test of time and retain a large active player base sixteen years after release. But not only has Age of Empires II endured, it has thrived. It’s gained new steam thanks in part to an official high-definition re-release but mostly due to the ragtag group of modders-turned-developers who made that release possible. Forgotten Empires filled the game with new stuff and rebalanced the multiplayer in one enormous mod and then two HD expansions: The Forgotten and the recently-released African Kingdoms. I spoke to the team to find out about the challenges of transitioning from mod team to professional development studio, and of continuing to expand a game within its ancient limits.

The team came together through the AoE2 community in 2011 after lead designer Bert Beeckman and various others finally figured out how to add new civilisations to the game. A few dedicated modders gradually morphed into many, and Forgotten Empires took shape just like any other modding project — a loose collective that grew and contracted fluidly as people gained and lost interest or time, and which, through sheer force of will from its lead developers, eventually emerged as a somewhat coherent thing. This particular thing was just more ambitious than most projects that reach fruition; it added five new civilisations with accompanying campaigns and unique units and buildings and maps and sounds. It was basically an unofficial expansion.

Beeckman tells me that it was fortuitous timing that got them in with Microsoft. “When we heard that the HD edition was going to be released on Steam, we’d kind of only just finished working on the Forgotten Empires mod,” he says. “We thought, okay, if you’re just gonna revitalise the game, why not go a step further and add new civs and features and new campaigns and all that new stuff we added [to the mod].”

They reached out to Microsoft. And waited. “They receive like hundreds and hundreds of mails each month from people who want to do things with the franchise,” Beeckman says. “Like oh I want to sell mugs of Age of Empires or I want to sell towels with a trebuchet on it. Can I do that?” Some poor sap has the job of trawling through these messages doing his best old-school Lara Croft impression (“No.”). But this time things were different. Forgotten Empires was a massive hit. Beeckman expected maybe 50,000 lifetime downloads, at best. It got that many in an hour (and their website crashed under the traffic load). Today the figure stands at around a million downloads.

Microsoft took notice and opened negotiations with the modders. They agreed to release an updated, more polished version of the mod as an official expansion. Thus the Forgotten Empires mod birthed the Forgotten Empires company, which in November 2013 released The Forgotten expansion — seven months after the HD remaster, 14 years after the original game, and 13 years after the previous expansion.

Several months after The Forgotten’s release, they petitioned Microsoft for approval to do an expansion for the then-new Age of Mythology Extended Edition. The answer was initially no, but Forgotten Empires kept asking. “Finally they said, ‘What do you think about making another expansion for Age of Empires,'” Beeckman recalls. “Then we kind of came back with, ‘Why don’t we do both?’ And then apparently one guy at Microsoft agreed with that.” (Their Age of Mythology expansion is nearly finished.)

It was a tough transition into professional development for many of the modders, and not just because of Microsoft’s fondness for firm deadlines. “When you are modding you can do awesome crazy stuff without caring if they will fit on the original game,” says lead artist Jorgito Ageitos. “You can put dragons in there and people will love it because it is a mod. But when when you are an official dev, a lot of things change. You have a lot of new restrictions that you didn’t face before and everything needs to make sense [and] fit in the game nicely with the rest of the stuff. And achieve that certain level of quality.”

Modding is a purely creative pursuit. You can express yourself, experiment, and have fun without worrying about how something fits with the rest of the game or even how good it is. You can, as Ageitos jokes, make a golden cow that wields a banana-shooting shotgun. It doesn’t matter if it’s in the spirit or the tone of the game. “I used to work always alone, so everything that I made in the past was ‘alright’ for me,” Ageitos says. “It was bound only to my own taste.”

But an official expansion needs to look, play, and sound like an extension of the original game. You have to cater to what the fans want, or at least what they’ll accept. Your taste becomes secondary to the original design principles and art style.

Beeckman says that the other hard adjustment was in legal rights. With most of the work already done, they had to retroactively negotiate terms with each of the dozens of contributors for rights to use their portion of the work. Some had trouble putting a figure on their time and talents, while others asked for “absolutely unreasonable figures” way out of proportion to their small slice of work. And some just walked away, not willing to turn their hobby into work.

For Beeckman, personally, it wasn’t much of a change. He already worked in the games industry at Nintendo Frankfurt (which does distribution and localisation rather than development), so he was familiar with how things worked. He’s now full-time at Forgotten Empires, as are the other “crucial” team members. He gives campaign designers as an example of people who aren’t yet needed on a full-time basis because there’s not enough work to give them. Regardless, he has his hands full coordinating a team of around 50 people plus 25 or so testers and localisers — all spread around the world in several different timezones as the studio has no central office.

The good news is that everyone on his team is a longtime Age of Empires fan. They know the game. They’re engaged in the multiplayer scene. That motivates them to make it brilliant. To fix both its most glaring and lesser noticed flaws. Like warfare on water. “If you see the original Age of Kings, which came out 16 years ago, water battles were essentially, okay, I make one boat and I put it next to my dock,” says Beeckman. “If somebody wants to attack me I will attack him back. That was it.” In the Conquerors expansion, Ensemble Studios added formations to naval battles but only offered one naval unit that was worth building. “People would make huge, huge fleets of galleys and nothing else,” Beeckman continues. “And that of course is not really good for a strategy game — just using one unit is detrimental to any sort of creative gameplay.”

For African Kingdoms, Forgotten Empires added new water units and designed them such that no one unit type is superior across all situations. Which fleet wins depends on a complex counter system that forces players to make combinations of boats and manoeuvre them around the map to get an advantage.

This particular change seems to be going down well with the community, as has the addition of “special” multiplayer maps that use unusual geography to break the predictable circular(ish) team placement — like an island for each player or two islands that each have three versus one matchups. But any change to the status quo threatens to splinter the player base. Any change — however small — to the design or art may, as Ageitos puts it, “cause a huge riot with pitchforks, fire, and people screaming.” People get attached to certain strategies and play styles, and that’s usually because those strategies are strong. Tweak a few numbers under the hood and you might just make somebody’s favourite tactic unviable, which will piss them off — especially if said tactic took years to discover and years more to master (apparently the most dominant pre-Forgotten strategies were only discovered four or fives years ago).

“At this point, especially with the African Kingdoms, we decided let’s ignore that,” says Beeckman. “If we can stick to the design principles like that every tactic needs to have a viable counter tactic, then we are in our right to change that.” Every design decision is a careful balancing act between keeping the peace with expert players, fixing old flaws, and improving the game’s strategic depth and balance.

Despite the influx of new, younger players that came with the 2013 HD remake, their focus is on balancing for the expert players. “There is a massive difference in play styles from the competitive scene to the casual scene,” Beeckman says. “Casual players usually like to build up all the way, slowly, down from the Dark Age all the way to the Imperial Age, then they start fighting. Competitive players fight as soon as they can. They sometimes even use villagers to try to wall each other in.”

It’s crucial to balance for expert play, because otherwise a few strategies will quickly become dominant, but Beeckman says “if you play on a lower level, the balance can always be beaten just by playing better. If you have a super overpowered unit or a very strong unit late game, like for example war elephants, then you just need to counter that by making sure that the opponent doesn’t get war elephants.”

Other lessons only came through making mistakes. “Everyone remembers playing William Wallace and hearing a guy try to pull off a Scottish accent,” says Beeckman. “It was hilarious. It made Age of Empires II so fun in a way. It was wrong, but it was good wrong.” The Forgotten didn’t have voice acting, and that (plus a more RPG-like quest structure) made its campaigns feel out of place. So voice acting became a top priority in African Kingdoms. As did polish in other areas. The expansion adds new environments, so they came up with new ambient sounds to distinguish these more strongly. And they tried hard to differentiate the look of the architecture and armour.

Ageitos pushes to make things look as close to the real thing as he can — because “history is fricken awesome.” While working on African Kingdoms, he looked at thousands of images to learn how and why they looked that way. Then wherever possible he remade them in-game. It wasn’t always possible, however, because even the HD version is essentially a 16 year old game made with the technological limitations of the time in mind. Both the original graphics and the prettified HD version of them hold up well enough, but they are nonetheless a relic of late-90s cutting edge 2D.

Or as Ageitos puts it, “That new ‘historically-accurate interesting-looking art’ needs to fit with the rest of the artistic world created by this game, and that is when the nightmare begins. Every new building for example [has to] have a certain size, certain proportions, key shapes and locations that you can’t just change as you see fit even if it will look completely awesome.” The new art has to fit the existing art, and that, Ageitos notes, is much trickier to do well than creating said art in the first place. He ended up doing some African Kingdoms art by measuring different parts from each of the original AoE2 buildings and then essentially chiselling away at cubes that fit these dimensions (a process described in more detail in this dev blog).

It’s hard to say how much further the creaking old AoE2 engine can be prodded and pulled and added to, and Beeckman isn’t sure if they’ll be asked to do a third expansion — or even if they’ll have enough new feature ideas and suitable civilisations to justify one. But even if this is it — no more new content, just patches to fix bugs and balance issues — Beeckman believes Age of Empires II will endure further.

“I think the current generation of people who are playing it will kind of play it till they’re tired of playing games,” he says. “People who grew up with Age of Empires will kind of keep playing Age of Empires.” They’ve already played for 16 years, so why stop now?

As for how it’s managed to endure this long, Beeckman pinpoints two reasons. One is that it aged well — most games from its time had ugly 3D graphics, but AoE2 had high-polygon 3D art rendered down to 2D sprites. The other is that the design encouraged players to make their own stories, to rewrite history or just have fun with the thousands of options and procedurally-generated maps. Whatever the reason, Age of Empires II is an enigma — a 16 year old game about historical warfare that refuses to take its rightful resting place in the annals of videogame history. And the Forgotten Empires team is its chaperone into old age.