Plumbing the depths of open-world space survival sim Empyrion's design

Empyrion – Galactic Survival is a game you might think of broadly as Minecraft with buildable vehicles and spaceships, and the ability to both travel to other planets and explore space, but with a great deal more to it than that.

The game has been in Steam's Early Access program for years, and over that time has drawn a large and devoted userbase. To better understand what makes it so enticing to specific players, Christoph Edelmann (of developer Eleon Game Studios) put together some answers to my questions about its construction and design.

The interview that follows has been lightly edited for clarity.

Who are you, and what is Empyrion?

Eleon Game Studios is a small team of professionals of game and/or software development, where the average team member has more than 10 years of industry experience. We are an independent game studio, so we are developer and publisher at the same time.

In 2013, we decided to start the development of a game that uniquely combines elements from space simulations, ego-shooters, construction games and survival games. In our youth, we were always disappointed that space simulations do not offer the possibility to land on planets, while ego-shooters do not allow you to get on a spaceship, leave the planet and explore a vast galaxy.  In addition, we like the gameplay offered by recent survival games as well as the freedom and creativity of games like Minecraft which allow you to design and build objects such as spaceships and bases freely.

As a result, Empyrion - Galactic Survival is designed as a 3D open world space sandbox survival adventure game, including a full single-player and multiplayer experience. You can build powerful ships, mighty space stations and vast planetary settlements to explore, conquer or exploit a variety of different planets and discover the mysteries of Empyrion.

One of Empyrion's stated design goals is to "make exploration interesting." What IS interesting? How does Empyrion make exploration interesting?

Only having to survive versus the environment is getting old, of course, as the basic survival gameplay cannot be stretched in the infinity in a space sandbox. At some point in the early game of Empyrion you will evolve from the point where you managed to serve your basic needs - and you need something else to do. A new challenge.

Knowing Empyrion would not be a game where you stay in your survival bubble at only one playfield or location, we started adding interesting locations and alien sites, so called POI (Points of Interest) early on. In this context, Empyrion is not just terrain, space and a few plants and animals dropped in the void. There are lots and lots of POI to explore. Starting from primitive villages to heavily defended fortresses and high tech space stations, everything is covered.

More and even entirely new types, like asteroid bases and secret artifact sites in space, are currently worked on by our very own 'Builders League' - an internal team of freelancers and volunteers that consists of experienced and skilled builders from the community.

This group is not only working on variants of the existing structures to offer even more variety for the players exploring our worlds, they are constantly building entirely new stations and large and exciting dungeons for space and planets. With our random distribution technique, we make sure the player running into these, is not always seeing the same POI in the same spot, or at least has a chance to see one of its variants. So if he is willing to spend some of his playtime on exploring the more than two dozen planetary and orbital playfield types (ranging from dense jungle worlds to hellish lava planets), he has a lot of things to discover.

And, in addition to the different POI, the playfield types pose a different challenge to the player each time as well. Furthermore, the missions a player can find on his way, will guide him through the solar system and throw even more and different tasks and challenges on him. The new faction system, where he can be friend or make foes with the currently three factions in the game, is adding the extra spice on top of that, as, if you annoy those factions too much, they will come for your base and try to crush you.

For us, making exploration an interesting experience, is a multi-threaded setup.

Empyrion has been in early access for four years now, and continues to be. How goes the march towards "official" release, and how has the long early access period helped and/or hindered you?

We are making good progress and we can say that we are coming closer to leaving Early Access.

The Early Access has definitely helped a lot, as it allowed us to develop our vision of the game together with the community. We are listening to their needs and they (often bluntly) tell us what they think about our feature additions. This works quite well, we think; it's often also more a feeling like working in the family company and telling the others what we have done...and then stand the feedback and often go on and in rare cases, roll back. We have also run several big surveys and we are constantly monitoring the feedback and the suggestions in our forums, on Facebook, Discord and other places.

This, on the positive side, has lead to a very dynamic development, which also allows us to integrate a lot of the feedback in a short amount of time. Of course not everything our community would like to see, is added to the game as fast as everyone would like to (we are currently monitoring a list of at least 400 minor and major requests!), and resulting from that, there is of course always some critiques like "why didn't you do this and instead added that."

This is possibly the only downside in such a community-driven development approach (and Early Access in general). But we are lucky, as we think we have an excellent community which wants to see the game grow for everyone and has a great consent in what we do or offer them. Especially as they know, features that are highly requested will be added sooner or later any hows.

There's a whole subgenre of survivalist building games from Minecraft on, like 7 Days to Die. But interplanetary survival? What prompted you to come with such an idea?

Back in the days when Minecraft started its popularity, creative people had already built space ships in that game for some time. Although they were static, the imagination of flying them out of the atmosphere has always been there. At the same time, space games have become popular again, after Chris Roberts’ Star Citizen created a hype and revived the whole genre–which was basically falling silent or even dead for years with no realistic chance for seeing the daylight ever again.

The sub-genre of space survival games was also starting to grow, but although there were already some great games out there, we did not find one that was combining the full experience of building, survival, space, adventure and exploration as we imagined it.

So having a game that would combine the creativity of Minecraft, the survival aspects of the genre and the freedom of space games, was not only a desire for us, but also a logical step. Although building your very own space ship, while you watch your oxygen and food-bar was of course a central point in the beginning, we never reduced the game to this element, but expanded its mechanics and grew it into a real space-survival experience, where you not only build and eat, but also have a lot of different ways to spend your time on experiencing your very own adventure in a dynamic universe.

There are a number of differences between your building model and Minecraft's, such as base limits and the fact that not everything is a cube. Structural integrity is one, how things that aren't or are insufficiently supported will collapse. How does this work, and how did you implement this feature?

On the first part of your question: yes, we do not only have cubic blocks. As of alpha 10, we now offer nearly 200 different shapes ( from cubic to rounded to spherical to exotic) you can build basic structures on one of the four available grid sizes: Small (0.5m blocksize) for Hover Vessels and Small Vessels and Large (2m blocksize) for Bases and Capital Vessels.

In addition each grid size offers several dozens of devices and machines and deco blocks that can be utilized for service, support, movement, combat and defense and beyond. And the amount is growing with each update, which leads to a increased grade of detail of vessels and bases, as everyone can see in the public workshop of Empyrion.

Structural Integrity (SI) is currently only a limitation for bases. It does not yet apply to vessels (as it is a bit more complex to add the same idea of having a 'breaking point' of some kind to moving entities). We added SI as a logical consequence of the game world and it was therefore introduced fairly early on. Although you can still deactivate SI, the limitation is also offering those that take care about what they do, a great way to show their building skills.

One needs to note that SI is not overly complex to understand and you can even activate a SI overlay that will show you the breaking points, for example for knowing when it is time to add another support beam or support structure. Of course it is also somehow satisfying to see your opponents turrets crumble to dust after you sneaked in and destroyed their foundations. As with any feature that is and was added in alpha up to now, the mechanics of SI could be subject to change (which means refinement and improvements) at any time.

What else does Empyrion have over other building/fighting games, such as Minecraft, Fortnite or 7 Days to Die? One sense that I get is more of an epic feel to it, since you can eventually build craft that take you off-world into space, build ships there, and even reach other planets, giving the player more long-term goals to reach?

This has a lot to do with the answer on the question how exploration becomes interesting. Adding to the answers given on that topic, so beyond POI, new worlds, playfields, faction interactions with real and ever-changing consequences to your action, the game is constantly adding new goals. Sometimes these are easy hurdles to overcome, like fueling your warp drive while you crashed on a planet you do not know. Or trying to solve a multi-staged mission that will give you more insight into the backstory of Empyrion–but also adds more questions.

We are currently also working on new methods to add more challenges in a dynamic way, so that the player which has overcome the basic needs of survival and has his ship ready and the will to explore, does not run into the same situation all the time. For us, this is a key element, to provide enough variety in any stage of the game.

Empyrion's huge and weird scope means the shape of the player's adventure's change as they play: first with plain old survival, then building a base fighting off drones, then constructing higher-level structures, then space travel. How do you keep late-game threats under control while the player struggles with early content?

Empyrion is of course not a funneled game world, what means that you could run into an opponent that you cannot beat at any time. If this would not happen, there would be no challenge and no need to learn from a defeat and thus no drive to improve your skills, knowledge or equipment. And of course, being prepared is a key element to survive–at any stage of the game.

For example, after you crash-landed on the planet in our default single-player scenario, you are in a more or less "safe" area, although it is not a safe zone. There is not newbie protection or shield or any other barrier. There are no really dangerous NPCs around (but some that will still kill you if you annoy them too much) and the equipment you get is laid out to deal with any of the early dangers. Of course, if you venture around, you will run into some serious trouble soon. To avoid that, we offer the non-experienced players a small tutorial, where they are guided to a save spot and told, how to create better weapons, food and stuff. If you follow these simple guides, you will manage to survive the early game.

At that point, the later-game threats, like a faction coming for you and trying to drive you from the planet, is avoided in a way that you first need to set them up with the things you do to them. So you will not run into a gun-blazing enemy capital ship while you make your first steps into this new world. If you leave your planet or grow your base, there are various indicators that your threat level towards a faction rises and if you can expect an attack.

At this point the player has already learned that killing an enemy might lead to an increased threat level for this faction and running a mission for the same faction might reduce the possibility of an attack–or make you even honored with them. So the control of the threats is at the hands of the player in a lot of ways. We are giving various info about his status towards any threat… but the rest is of course common sense and maybe a will to face the dangers and learn from failures–so they do not happen the same way again.

In Minecraft, many of the recipes make physical sense, like Sand + Gunpowder = TNT. How is Empyrion's resource tree geared towards gameplay versus realism?

Empyrion has–what we think is –a good mixture of both, although we bend the reality a bit more than maybe Minecraft or other more real-world survival-focused games. The focus of our game is, that players have fun. We do not want to annoy them with too much reality. It is a sci-fi environment after all. Throwing stuff in a constructor in order to get a device which–when placed–might be larger than the constructor itself, is possibly a bit abstract, but the Sci-Fi movies and literature also gives us a lot of possibilities to explain that. From hammerspace dimensions to on-site nano assembly–we think the excitement of something that sounds reasonable enough to work with the current sci-fi themes is nicer, than something that needs to work with actual science.

Although there are no real world examples on how a anti-gravity field works, or a gravity generator or warp drive or what elements they consist of, this is often discussed in the forums–but in context what we have created in the world of Empyrion so far.  Although things like aerodynamics and mass and volume, which have a closer relation to reality, even for these topics it is more important for the community that their stats make sense in the game, than being overly "realistic." Maybe we can put it like this: If something is consistent in its explanation, it is not a problem, if it is not really realistic.

In the world of Empyrion, resources and mechanics are more or less judged on the basis [of] if they apply to any given sci fi universe more than the real universe. Of course we have iron, copper, cobalt and some of the more real-world devices, like ammo and weapons, are made of materials like steel and copper. Also machines that have a hull are made from metal or plastic, so the exotic components that sometimes add some "magic" to a device are used at points where you do expect the fiction, not the science.

Sometimes we lend some names and properties from elements that are not that common. For example Promethium, the basic 'fuel' in the game, is a fission product of uranium in reality. So in the game, the material is also used in the context of powering devices and it is radioactive. So, on a more global level, there is an inner logic connecting all of these elements in that way.

They all have properties that derive either from real-world examples (or their meta) or are common sense of sci-fi and are used where they are expected–like crystals are used in energy weapons. There is no magic spell or hand waving where the player could feel disconnected or an abstract entity.

For us, this is a good approach, and often the only possible to make the game fun and not annoying. Who wants to do space battles with no laser effect and without warp drive? Or the other way 'round: who would not expect some exotic materials in a sci-fi base game? For a game like Minecraft or 7D2D which is very closely situated in the real world, these excuses would of course be more problematic. But for a space game, they are more or less expected and necessary–as long as they make sense in the game context. And as long as they are fun and not annoying.

There is a great aspect that feels a bit like Kerbal Space Program, when descending to a planet's surface and you see locations marked in the far distance. Do you see any similarities between your game and that of the intrepid Kerbals?

Yes and no. Of course Kerbal Space Program is a bit more about the simulation aspect (and the construction), but of course the visuals are equally important. As soon as you enter  the atmosphere of a planet in Empyrion, details of the surface are popping up, like terrain, trees, lakes and of course other details like POI and other interesting sites. This adds a lot to the atmosphere of the game, as you recognize the world you are about to land on, is a living and breathing (and somehow covered with settlements) planet. Add in a dramatic sunset or sunrise while you descend to the sinister alien base on a white beach, and you got the feeling of being a real space adventurer.

Did you have any difficulties in implementing the multiplayer? Any particular design challenges you had to overcome? Can players explore different planets in the same game universe simultaneously?

Yes, all the mentioned features have been working pretty much from the beginning. As soon as we added the dedicated server technology with one of the first alpha releases, any player could explore planets and orbits simultaneously and on their own. In the early days of the (non-official) closed alpha, players had to be in the same playfield or cross the playfield borders, being seated in the same vessel, for example when going from orbit to the planet or vice versa. But this was one of the first challenges we solved before we even went live on Steam. The playfield techniques added back then have the big advantage that single-player and multiplayer share the same architecture.

So you can resume a single-player save game with your friends in co-op or upload it to a dedicated server, while you can always resume a coop or server session in single-player (if you got the save game files). And of course the development only has to take care of one method of how things need to be done, not different ones.

A small downside has been that playfields are currently separated instances, so a warp jump or landing on a planet is not a 100% fluent experience but has some minimal loading effect. Said that, and especially for the planet<->orbit transfer, we are currently investigating new solutions. And also for space, which is currently a giant cube, we are looking into techniques to make it feel really "endless."

Empyrion is a game with big ambitions, and it's already implemented some of them. What are your plans for the future?

Currently, at the moment we got this interview request, we are working on the 'mid-version update' Alpha 10.5. while planning our next steps for upcoming updates. These updates will bring some larger feature changes again and fill in some of the missing (or not yet revamped) features to the game such as research, a skill system, multi-solar system, modding API improvements and more.