A game with generations of explorable content is getting even bigger

Elite: Dangerous is big and, if we're being honest, calling it big is an understatement. The spacefaring game — which is live now on PC, Mac and Xbox One — contains hundreds of billions of star systems. That's not a typo. Players can travel to each of those systems and orbit multiple planets within them. Along the way they can interact with political factions, pirates and bureaucrats on an intergalactic scale.

But there's been a certain lack of intimacy to the massive game. Some would say that there's not an awful lot to do. That all changes next week, when the Horizons expansion enters beta testing on Windows PC. The paid add-on to the base Elite: Dangerous experience fulfills a Kickstarter promise to finally add planetary surfaces to the game. That includes everything you might think would go with it; landing on planets, flying into surface settlements and driving around in ground-based vehicles. How big of an expansion is it? "If you took Saturn's orbit," said Matt Dickinson, Elite's head of technical art, in a recent interview with Polygon, "and filled it in like one big plate, that’s the surface area we’re creating. It’s massive. "If you take all the 400 billion star systems, all with however-many planets orbiting around their associated suns and things, about 60-some percent are going to be landable in Horizons when we launch." Think of every known and unknown star system in our galaxy. Then, consider only those which lack an atmosphere — no oxygen, hydrogen, no nothing. You'll be able to land there, and alongside your friends explore those places for the first time. It's quite possibly the biggest game expansion, in surface area, ever conceived. And it's just around the corner.

Details, details Everyone Polygon talked to at Frontier Developments seems to be hedging their bets with Horizons. That's because no one has the time, or indeed the lifespan, to visit all of the square footage that's being added to the game. Each planet that's being added is procedurally generated, and it will be up to players to discover and explore them all for the first time. So in actuality no one at Frontier really, truly knows how big an expansion Horizons really is. "To get all physical," said Dickinson, "a lot of the stars near the core of a galaxy don’t have planets around them because they’d just be ripped apart by the gravity. ... Someone [at Frontier] did think of a number of planets in the expansion and it was terrifying." The Stellar Forge is Frontier's proprietary tool for creating our universe. It's already generated the star systems that make up Elite's playspace. Now, a secondary system is working to generate the actual shape of the surface of a portion of those planets, but it's also seeding them with all manner of interactive gameplay elements including starports, settlements allied to a particular in-game faction and AI-controlled drones. And all of this is being generated in the background, largely obscured from Frontier's oversight. "Procedural generation," Dickinson said, "is sort of artist-focused. We’ve tried to understand the formation of planets, the layers that are built up and the processes that go on — the geology and things — and how we can replicate that. No one at Frontier really, truly knows how big an expansion Horizons really is. "We’ve talked about the base of a lot of planets. We call it the tectonic mask ... We generate these tectonic masks, which on Earth would give you continents and things. We understand the compression of the plates, so we can see where they’d move together and move apart. That creates where ridges are formed, mountains, or trenches, oceanic trenches on Earth. Those sorts of things. We can use that to build up the geology of the planet. We can add impact craters and other things. Then we can use the minerals and what’s in the planet to determine the colors and some of the process. So you’ll have rocky worlds, ice worlds, metal worlds." Players will be able to land on a planet, look up at its orbiting moons and know with a kind of certainty that they can set foot on every square mile of landmass visible to them and experience it first-hand. "You’ll be able to look up in the sky," Dickinson said, "and instead of having the textured sphere you’ve got now, that will be another actual world. You can look up and see the mountains and the craters being shadowed by that sun, and if you get bored of moving around the particular planet you're on you can point your ship up there, fly there seamlessly, land in that crater that you saw and drive around."

What is it that you do here? Horizons is more than just a geographical expansion. It's a gameplay expansion, adding new and unusual flight mechanics to an already challenging game. Elite famously asks players to land their hard-earned ships inside massive, spinning space stations. It can be challenging, even when using a joystick and throttle. Horizons will add another kind of craft to the mix, the rocket-powered, wheeled rover called the Scarab. But the closer you get to the surface, the more challenges arise. "Each planet has its own gravity," Frontier lead designer Sandro Sammarco told Polygon. "It’s not all the same. It does have a big impact on your driving model. The Scarab has a whole suite of thrusters; big thrusters on the back, and little wheel-based movable thrusters as well. Clearly you can do giant leaps with the big thrusters and that’s a lot of fun. If the gravity is low you can get terrifyingly high air. You can jump high enough that it becomes dangerous on the way back down." "In hindsight it’s obvious that different gravity levels don’t automatically mean more fun." But not every planet is Earth-like, and those differences in gravitational pull can make for some exciting and unusual gameplay hurdles. The team behind Elite has had to take some liberties with the design of the Scarab to keep the game playable. "These wheel thrusters," Sammarco said, "allow us to give more grip when the gravity is low. One thing we found out very early — in hindsight it’s obvious — [is that] different gravity levels don’t automatically mean more fun. It’s just different. When we were driving in gravity levels that were something like 0.1 Earth gravities, you would think that would be great, but it’s not. It’s awful. You’re driving along and the moment you hit any tiny little outcrop, say goodbye. You go flying off into space. "So, the Scarab inherently has mechanisms that are not only technically correct, but they’re there so you can have a fun time. These wheel-thrusters basically act like downforce. They push you onto the floor."