Alpha 16 on public unstable branch (updated)

Posted December 12th, 2016 by Tynan Sylvester

UPDATE: Unstable version is being updated more or less (week)daily. The forum thread has the ongoing discussion and update details.

Alpha 16 release is upcoming. If you are on Steam, and in the middle of a game, please use the Steam betas feature to set your game to the “alpha15” branch. This will prevent it from automatically-updating to A16 upon release and breaking your save games.

If you’re willing to play with bugs and imbalances, and to have your saves broken randomly and without warning, you can now test the unstable version of Alpha 16! Just load the the ‘unstable’ branch on Steam. (To access the unstable branch, right-click RimWorld in the Steam library, open Properties, go to the Betas tab, select the ‘unstable’ branch, and restart Steam.)

This isn’t a ‘real’ release, and if you want to play the bug-free update you should retain your hype and wait until it’s properly released!

Please leave balance and design feedback in this forum thread. I’m especially interested in play stories around the new world system. Bugs should please be reported in the Bugs forum.

Modders can use this opportunity to prep their mods for the new update! Translators can use it to translate (there is a new translations tool; access it by turning on dev mode and hitting / in the main menu).

I’m also requesting that video makers, YouTubers and streamers please not make videos of this release. I don’t want to leave false impressions with a buggy and unbalanced unstable version.

There’s no change list yet; I plan to release that with the stable Alpha 16 release. Note that not all player content is included yet.

Thanks to all those who test and give feedback!

(I am deliberately not announcing this everywhere at once because I want to be able to draw in more fresh testers later as needed.)

Quick teaser: Transport pods

Posted December 1st, 2016 by Tynan Sylvester

Currently bugfixing and tuning Alpha 16. Here’s a new teaser!


Some fun teaser images

Posted November 4th, 2016 by Tynan Sylvester

Hey all, just some quick teasers for you! (Edit: new ice planet shot added!)


I’ll be releasing more information about this soon-ish. I just wanted to give you all an image so you know we are still working at full steam, on many different features.

A16 will probably be the biggest update ever in terms of the amount of work we’ve done adding and refining things, so it’s taking a while.

Steam access now available for DRM-free purchasers

Posted October 5th, 2016 by Tynan Sylvester

We’ve worked out the kinks since the last update, so now all purchasers buying the game off can immediately register their copy on Steam through

This is better than buying on Steam for a few reasons:

  • You get Steam access either way.
  • You get access to the DRM-free version as well, which can be useful.
  • You get access to the Prototype Pack of games that eventually became RimWorld (not available on Steam).
  • You get the warm fuzzy feeling of helping out a developer. Ludeon gets almost all the money you pay to buy DRM-free copies, whereas we get much less when you buy through Steam.

The way the new system works is that it doesn’t give Steam keys. It registers the game directly on your Steam account. I’m hoping this will make scamming infeasible. But, we’ll be watching in any case and will be invalidating any keys or accounts that were bought using stolen credit cards or through other chicanery.

New Steam registry system in testing for those who bought before today

Posted September 30th, 2016 by Tynan Sylvester

I’ve always wanted to give Steam keys to all players who buy the game on our website. Unfortunately we had to disable that after scammers attacked the site and started harvesting thousands of dollars in games using stolen credit cards.

But no more! Web dev Hypolite has developed a new Steam registry system that directly connects to Valve’s servers and registers the game directly to your Steam account. This makes it impossible for scammers to harvest Steam keys they can re-sell.

The system is currently in testing, and will work only for users who bought up to the end of September 29, 2016 UTC. So, if you bought the game DRM-free before today, I invite you to go to the new Steam registry page and register your game on your Steam account.

Once testing is complete, we’ll be able to offer Steam access to all buyers of the DRM-free version.

Creative content rewards available separately from main game

Posted September 9th, 2016 by Tynan Sylvester

You can now buy the creative content rewards separately from the base game! This has been requested a few times, and now it’s possible.

Creative content rewards are things like Name in Game or Pirate King that allow you to put your own character content into the game through our automated Creative Rewards System. Previously these could only be purchased in packs with the main game. Now, you can purchase them separately, on Steam. They are:

Name in Game Access

Backstory in Game Access

Pirate King Access

Hope you like them!

Note: These upgrades are only available on Steam for now, DRM-free sales are still by package only.

Alpha15c is live

Posted September 2nd, 2016 by Tynan Sylvester

Alpha 15c is live on both Steam and non-Steam downloads. Non-Steam users can get it, as usual, by re-downloading from their existing download link.

The details for this update can be found on the unstable testing announcement post.

Many thanks to all the testers who made this possible!

Alpha15c in testing on unstable branch

Posted August 31st, 2016 by Tynan Sylvester

Alpha15c is currently on Steam’s ‘unstable’ branch for public testing. This update fixes some important bugs and yield significant CPU usage optimizations. It also adjusts a few balance points for a better experience. I invite everyone willing to choose the unstable branch and test it out! I invite feedback in this forum thread and in the comments here.

Save compatibility: Savegames from the unmodded game will be compatible from earlier Alpha 15 versions.

Mods compatibility: Data and XML mods will be 100% compatible from earlier Alpha 15 version. The API for code mods is also unchanged, and so should remain compatible. However, since the core game has been recompiled, some mods may need to be recompiled as well before they work again. Mod authors may want to look at Alpha15c to check and prepare compatibility. (This shouldn’t require any actual code or data changes, but may require recompiling your code).

Once Alpha15c is confirmed stable, I will release it to all users. Hopefully within a day or two.

Detailed change list:

  • Fix: Luciferium is not addictive; it gives the positive effect forever with no downside.
  • Fix: Malari-block high never goes away.
  • Optimized a bunch of pawn ticking code to be much, much faster.
  • Rebalanced drugs to be a bit more profitable and a bit more more dangerous.
  • Food selection algorithm prefers meals by 16 cells instead of 7.
  • Fix: Game doesn’t assign short hashes if you subclass any Def class. This makes many mods impossible.
  • Fix: Standing lamps and sun lamps are available without research.
  • Fix 2618: On Linux, system language can break the game.
  • Fix: Raiders can steal during tutorial.
  • Fix 2620: Learning Helper: Items remain after save-scum.
  • Fix 2611: Scenario ‘Can’t Hunt’ etc doesn’t work.
  • Translations update.
  • Some other misc minor fixes, rebalancings and text changes.

Alpha15b – Tiny fix to early game raid timings

Posted August 29th, 2016 by Tynan Sylvester

A tiny update to Alpha15b has been released that fixes a small bug with Cassandra Classic and Phoebe Chillax.

DRM-free players can update by simply re-downloading from their existing download link. It always carries the latest version. (Don’t worry about running out of downloads, you can always email support for a reset. We just have that limit to stop automated abuse.)

These storytellers were miscounting the days since game start, and so were sometimes incorrectly sending a several raids in the 5-10 day range, making this crucial part of the early game far too hard.

This update is tiny (two lines of code) so it shouldn’t affect compatibility with saves or mods.

However, because it will shift the storyteller’s timer, it may cause some players to get a string of raids in a row, or a long peaceful period. This will only happen once.


Alpha 15 – Tutorial and Drugs released!

Posted August 28th, 2016 by Tynan Sylvester

I’m happy to announce that we’ve just released RimWorld Alpha 15! This version adds a rich tutorial, an intelligent learning helper to help you pick up the game, a new drug system, deep drilling to provide resources in the end game, and a giant pile of other smaller improvements and fixes. A full change log and detailed info is below.

For Steam players, if you want to continue with Alpha 14 for any reason, you can get on the ‘alpha14’ beta branch in Steam. In the Steam Library, right click RimWorld, click Properties, go to the Betas tab, select alpha14 in the drop-down list, and restart Steam.

Non-Steam players who wish to update can simply download from the same download link as before; it has been updated to the new version. They should install the new version in a clean empty folder.

Save compatibility: As usual, Alpha 15 will not load Alpha 14 save games by default. However, a user did put together a guide that allows you to manually update save files with some text editing. Check it out here if you really want to try to continue that Alpha 14 colony.

Mod compatibility: Some purely XML mods will be compatible between versions. However, most significant mods will need to be adjusted and recompiled. Beware: If a mod author updates their existing mod to the new version, it’ll stop updating on the old version. You may wish to turn off Steam auto-updates if you really want to avoid this.

Change list:


  • Added new rich tutorial with step-by-step instructions.
  • Tutorial teaches the basics of setting up a game, building a small self-sustaining colony, and defeating the first
  • Tutorial locks out irrelevant controls and highlights relevant controls.
  • At the end of the tutorial, the player can continue the game with a normal storyteller.

Learning helper

  • Added new learning helper system to replace yellow pop-up messages and yellow learning alerts.
  • Learning helper sits in the top right of the screen. If something happens relating to a concept the player hasn’t learned, that lesson will be activated and shown on the learning helper. It can then be opened and read. Lessons are automatically marked as learned when the player does the necessary interaction, and can be marked as learned manually. Lessons are shown as needed by circumstance, or on a slow timer. The overall idea is that you’ll never be shown a lesson you already know, but always be shown the lessons you need to know now.
  • Learning helper can be expanded and searched for any lesson, so you can look up how to do a specific thing at any time.

Drugs system

  • Added new drugs system. It’s not just beer any more!
  • Drugs typically create up to four effects. Not all drugs have all effects.
    • Primary – The valuable short-term effect, whether it improves mood or work focus or combat effectiveness or makes one immune to a disease.
    • Overdose – Excessive drug usage in a short time can build up blood toxicity, leading to unconsciousness and possible death.
    • Tolerance – Long-term usage of a drug can build up a tolerance which makes subsequent usage less and less effective in producing the high.
    • Addiction – Drug use can form an addiction. This generates a new need for the drug which the pawn will try to feed regularly. If the need isn’t fed, the pawn will develop withdrawal symptoms (low mood, reduced consciousness). Eventually withdrawal will pass and the addiction will go away.
  • Drugs can be assigned for regular taking through the drug policy system. Similar to Outfits, drug policies are an assigned schedule for taking drugs. You can set any number of drugs, each with a frequency. For example, you can assign a colonist to drink 2 beers every day, and take one Malari-Block every 5 days.
  • The drugs are:
    • Beer – Improved mood but worsened capacities. Addictive.
    • Malari-block – Prevents malaria infection for 5 days.
    • Yayo – Stimulant pleasure drug, addictive.
    • Flake – Cheap, short high, very addictive.
    • Wake-up – Improves work performance, addictive.
    • Smokeleaf – Improved mood but worsened capacities. More hunger, slower movement. Can form dependence.
    • Go-Juice – Synthetic futuristic combat drug. Boost speed and fighting capacity tremendously. Addictive.
    • Luciferium – Glitterworld mechanites that give huge bonuses to most capacities. However, without repeated doses the user goes insane and dies. It is impossible to clear the addiction, and the drug is 100% addictive on one dose.
  • Drugs are produced in various ways, typically at the new Drug Lab building, from various precursor chemicals and growable crops. They require research to create.

Deep drilling

  • The map now spawns with clusters of underground resources. These can be accessed by building a deep scanner to find them, and then building deep drills on top of them, and then working the drills. This slowly produces the resource.
  • Deep drilling tech is at the end of the tech tree. This should mitigate late-game resource exhaustion problems.


  • Mood is now drawn subtly behind the pawn on the colonist readout at the top of the screen.
  • You can now produce medicine from herbal medicine, neutroamine (a precursor chemical you buy), and cloth. Requires research.
  • Added passive cooler building. Made of wood and low tech, it cools a room for a short time. Good for passing heat waves as a tribe.
  • Added a ‘copy building’ tool which lets you quickly select the designator for a building through an existing copy of that building.
  • Beer production now takes several stages: Colonists make wort (unfermented beer) at the brewer table, then leave it in fermenting barrels for a while, after which they can harvest it as beer.
    Infestation can now only spawn under a thick roof.
  • Gear tab now shows aggregate stats about armor and comfy temperatures.
  • Raider steal a bit more often now.
  • Factored MapGeneratorDef apart into separate GenStepDefs which can be modded or inserted individually. This will allow modders to change the MapGenerator without blowing away each others’ changes.
  • Added alert: Need warm clothes.
  • Mods can now be dragged to reorder them in the mods page.
  • Re-tuned food finding algorithm.
  • Hunters will no longer hunt without a ranged weapon.
  • Debuffed corn a bit.
  • Reworked trade interface to clearly state what kind of trader they are, and to list items they’re not willing to trade.
  • Reworked trader stock generators so traders carry and accept more sensible items for their type.
  • You can now request traders by calling allied factions. It costs silver.
  • Chance to spring known traps is reduced from 2.5% to 0.4%.
  • Friendly fire chances reduced by 60% for fly-by shots (shots that miss and land in the cell with a pawn have the same chance to hit as before).
  • Added a message when food spoils in storage.
  • Fix: Pawns don’t get ‘catharsis’ mood gainer thought after a mental break.
  • Rename PDW to Machine pistol.
  • Torches and campfires are no longer destroyed near-instantly by rain/snow. They instead consume fuel faster.
  • Torches consume fuel a bit faster overall.
  • Fueled generator consumes fuel faster and holds less fuel.
  • Plant sow and harvest are now slower.
  • Debuffed fists.
  • Reduced volume of idle animal calls at high time speeds.
  • Smithing is now a prerequisite for Machining research.
  • Added a toggleable view that shows roofs in glowing green.
  • Hundreds of other balance changes, text fixes, redesigns, and bug fixes.