Offworld Trading Company‘s first expansion pack – Jupiter’s Forge – was released today. Buy it here on Steam.

Jupiter’s Forge, the first expansion pack to Offworld Trading Company, is our chance to see just how flexible free-market game mechanics can be. During development of Offworld, we discovered that the core gameplay was remarkably robust because the buy/sell mechanic auto-balances the game. Thus, the game should be just as fun even if the map, the HQs, and even the resource tree changed significantly.

Reworking the resource tree would be the most significant change as everything in the game is downstream from how the resources interact. We knew this change should not be minor, so we looked for a location in the solar system that could flip the water tree, which led us to Io, a moon without water but with sulfur oxide ice and a steady stream of hydrogen ions from the neighboring planet. Here, instead of splitting water into oxygen and fuel (hydrogen), the player would melt the ice for oxygen, collect hydrogen from Jupiter’s radiation, and combine them into water. Life support becomes much more challenging when the player can’t just extract water straight from the ground.

Io has a few other wrinkles that mix up the familiar formula from Mars. The day is much longer – 42 hours! – with an additional two-hour eclipse when Jupiter blocks the sun. From the Ceres DLC, we are borrowing diminishing resources (which drop high and medium tiles to low over time) and cave terrain (which gives mining access to all adjacent tiles). Because Io has no atmosphere, wind turbines are not buildable, so players must rely on geothermal plants, solar panels, and nuclear energy. Io also has liquid basalt lakes, on which players can build basalt platforms that produce iron, silicon, and uranium. (Further, scientists can use these resources as inputs for their buildings.) Finally, Io has an assortment of random event new to Offworld – radiation storms, sulfur frosts, landslides, and tremors. The Patent Lab on Io has some new options as well: Nuclear Engine (use uranium as fuel), Geothermal Borehole (all buildings adjacent to geothermal tiles produce power), and Synthetic Meat (farms are permanently boosted).

We also knew that we wanted to encourage new ways of approaching the game by adding two new HQs to the game. The Penrose Collective (colloquially known as the Nomads) are scrappy survivors, emphasizing flexibility and adaptation by allowing the player to actually return claims back to the colony to grab new locations. If aluminum crashes, return you aluminum tiles and get into something more profitable. The Nomads also are able to place two HQs on the map, which reduces their shipping costs and makes moving claims around easier. Finally, the Nomads use silicon instead of steel as their primary resource, making them a good choice for maps rich in the former resource.

The Diadem Trust (known as the Elites) are thematically the rich kids of Io, focusing on special versions of all the advanced buildings. Their Pleasure Dome produces double the revenue (but consumes chemicals); their Patent Lab can license patents from other players; their Optimization Center grants free claim for each fully upgraded resource; and their Hacker Array can create a shortage and a surplus simultaneously. Finally, they can build three Space Elevators instead of the typical two. (Oh, did we mention that Io has a Space Elevator instead of an Offworld Market?) Thus, the Elites are difficult to stop if they make it deep into the game (although that itself can be a challenge as they have few early bonuses).

We hope players find Jupiter’s Forge to be a fresh experience that makes them rethink their old strategies from the base game.

I spoke at GDC this month on the design and development of Offworld Trading Company, and video of the talk is now available online:

Slides from the talk are also available.