A Man and His Dog

Posted August 27th, 2015 by Tynan Sylvester

Fan video by IskOtter.

Hotfixed to Alpha12b (now Alpha12c)

Posted August 26th, 2015 by Tynan Sylvester

I’ve just uploaded a hotfix to version Alpha12b. This is purely a fixing and balancing hotfix.


  • Your saves from A12 should still work. Hooray!
  • Data/XML-only mods from A12 should still work. Yay!
  • Mods with code from A12 may work, or they may break. You may need to recompile them with the new DLL. Aww.

To get the update: Download using your previous link from your last email and install to a clean empty folder. There will not be a new email sent. Your personal download link is permanent and always has the latest version. If you need help with anything, please go to ludeon.com/support.

Changes in Alpha12b:

  • Rebalanced animal hauling, traps, charge rifle, assault rifle.
  • Rebalanced animal hunger rates and plant nutritions so animals need larger grass pastures to be sustainable.
  • Thrumbo is much more powerful in combat.
  • Sleeping pawns now wake up when harmed.
  • Float menu column is wider to avoid cut-off text.
  • Ship part incidents won’t occur so early.
  • First raid comes a bit earlier on Cassandra and Phoebe.
  • Fixed: Manual work priorities being used after switching to non-manual priorities.
  • Fixed: Colonists have ‘colonist left unburied’ thoughts when tame animals were left unburied.
  • Fixed: Eggs can only be used for simple meals
  • Fixed: Trade items dropping in weird places.
  • Fixed: Colonists incapable of violence can slaugher animals.
  • Fixed: Alphabeavers leave the map after they sleep because they get hungry.
  • Fixed: Date changes over at 6am, not midnight.
  • Misc other fixes and improvements.

Change in Alpha12c:

  • Poison ship part event now only drops one ship part instead of 2-3.

RimWorld Alpha 12 – Animal Taming released

Posted August 21st, 2015 by Tynan Sylvester

Animal taming is here! You can now tame animals, milk them, eat them, and train them into whirling furry/scaly death machines! We’ve also added codified room roles and statistics (like room wealth and room impressiveness), new traits, animals, threats, items, bonuses, bugfixes, and bugs. A full change list is at the end of this post.

How to upgrade: If you own the game, you can get the new version by re-downloading from the link you used before (it is a permanent link and always has the newest version). You should also get an update email from us. Anyone still having trouble should start at the support page which includes an automatic link sender tool and our support email. There may be a delay of some hours before your download count resets or your email arrives.

Also note that this build will not load old savegames or old worlds, so please don’t try to load these in the new version. They’ll probably just crash the game.

Change list:

Animal taming

  • Colonists with the Animal Handler work type will now interact with animals.
  • Animal handling success rates are governed by the new Animals skill.
  • Handlers can tame animals. They approach designated wild animals with food and attempt to tame them to make them part of the colony.
  • Handlers can train animals as designated in tame animals’ Training tab. Animal training looks like taming, requires food, and trains one “trainable skill” at a time. Not all animals can learn anything; they need sufficient trainable intelligence.
  • Trainable skills:
    • Obedience: has master, follows master while master is drafted and defends him.
    • Release: master can release animal during combat to attack distant enemies, and call animal back.
    • Rescue: animal will rescue wounded colonists and take them to bed. Animal must be smart and large enough to do this.
    • Haul: animal will intermittently haul items like a colonist would. Animal must be smart enough to do this, and will haul an amount related to its body size.
  • Added Animals main tab, which lists all colony animals and provides interfaces to set their master and area restriction.
  • Each animal has a ‘wildness’ indicating how difficult it is to tame.
  • Animals have a minimum handling skill. Player is warned if they designate taming an animal that no handler can actually tame.
  • Tame animals can be assigned animal areas in which they will try to remain.
  • Tame animals can be bought and sold. Bulk traders carry normal animals, while exotic goods traders can buy and sell any weird animal, pre-tamed.
  • Tame animals can be designated for slaughter and animal handlers will slaughter them.

New animal behaviors and mechanics

  • Some animals (alpaca, muffalo, camel) can be shorn for wool that can be crafted into apparel.
  • Some animals (muffalo, cow, camel) can be milked.
  • Some animals (chicken, cobra, iguana, tortoise, etc) can now lay eggs. Fertilized eggs will hatch. All eggs can be eaten or cooked.
  • Animals can be pregnant and give birth. Animals are made pregnant when a male approaches and mates with a female. Birth is accompanied by amniotic fluid spray.
  • You can now build animal beds and animal boxes and place animal sleeping spots.
  • Animals all sleep.
  • Animals can have different graphics per gender.
  • Animals have “life stages” related to their ages. Baby animals are tiny and weak, juveniles somewhat larger, and adults are full size.
  • Colony starts with a random pet.
  • Animals can nuzzle colonists, improving their mood.
  • Animals can be named when tamed or when nuzzling. Names are drawn from a large bank of animal names.
  • All organisms including animals have life expectancies and will develop chronic conditions like frailty or cataracts in old age.
  • New incident: Farm Animals Wander In (some tame farm animals wander to and join the colony)
  • New incident: Self Tame (random wild animal on map becomes tame).
  • Doctors will treat animals’ wounds if the animal is in a colony bed.
  • Some animals may attack on a failed taming attempt.
  • Animals produce animal filth, proportional to body size, inversely proportional to petness.
  • Tons of new animal graphics and sounds for new animals.

New animals

  • Boomalope (large fragile animal that explodes and sets fires on death)
  • Thrumbo (giant peaceful powerful creature with amazing fur and horn)
  • Chinchilla (very valuable fur)
  • Capybara
  • Cow
  • Pig
  • Chicken
  • Yorkshire terrier
  • Labrador retriever
  • Husky
  • Elephant

Room roles and stats

  • Rooms now have ‘roles’ and stats based on what is inside them. These are automatically-defined values that, in turn, passively affect thoughts and events in the room.
  • Room roles and stats can be inspected with a new inspection tool (bottom right of screen).
  • Room roles are:
    • Bedroom
    • Barracks
    • Prison bedroom
    • Prison barracks
    • Dining room
    • Hospital
    • Laboratory
    • Kitchen
    • Rec room
    • Tomb
  • Room stats are:
    • Impressiveness (most important stat; an aggregate of other stats, mostly for pride psychology)
    • Wealth
    • Space
    • Beauty
    • Cleanliness (has a direct effect on medical outcomes)
  • Room stats affect things like:
    • Immunity gain speed
    • Medical treatment quality
    • Room stats create many variants on thoughts like:
    • Ate in impressive dining room
    • Own impressive bedroom
    • Own bed in impressive barracks
    • Did joy activity in impressive rec room
  • Added traits:
    • Greedy: Unhappy without a very impressive room.
    • Jealous: Unhappy if anyone has a room noticeably better than him.
    • Ascetic: Unhappy unless he has a very crappy room.


  • Added ‘facilities’ – passive buildings that give bonuses to nearby buildings:
  • Vitals monitor (improves healing in adjacent medical bed)
  • Tool cabinet (improves production at nearby work table)
  • Multi-analyzer (speeds research at nearby research bench)

Ancient artifacts

  • Ancient artifacts with psychic powers can be bought, sold, and found in ancient crypts.
  • Psychic powers work at any range through obstacles.
  • Artifacts are one-use.
  • The artifacts are:
    • Psychic insanity lance – drives a single target insane
    • Psychic shock lance – drops a single target asleep
    • Psychic animal pulser – drives animals berserk map-wide
    • Psychic soothe pulser – gives a temporary mood boost to everyone on the map

Graves and sarcophagi

  • Graves are no longer just glorified storage slots; colonists must actually ‘bury’ corpses.
  • Can now build sarcophagi out of solid materials. High-quality sarcophagi are art items.
  • Colonists will visit graves of dead colonists for a joy activity.

Misc new incidents

  • New incident: Poison ship. A variation on the psychic drone ship that kills plants in an expanding circle.
  • New Flashstorn. A localized, intense lightning storm in one area of the map. Causes big fires.

Interface rework

  • Main tabs like Work, Outfits, World, Factions, etc are now tabs permanently displayed along the bottom of the screen instead of being buried in an Overview window.
  • Some tabs, like Work, will not take more space than they need to given the number of entries (colonists) to display.


  • Added heart attacks. People or animals approaching or past their life expectancy will have a chance of heart attack, which will progress and resolve in a random way. Heart attack is emergency-treatable to improve outcomes.
  • Added hay (animal food only, for getting through winter). Added haygrass (long growing, high yield of hay).
  • Added way to enable/deny medicine in different qualities to any colonist, prisoner, or tame animal, from a the health tab.
  • All furniture is now ‘minifiable’ like televisions and telescopes. This means beds, chairs, etc can be moved without being rebuilt, bought, and sold.
  • New trait: Night owl. Happy when awake at night, sad if awake around midday.
  • New thought: Crowded – In a space with too many people.
  • New installable implant: Painstopper. Prevents all pain, but reduces consciousness permanently.
  • New installable implant: Joywire. Large permanent happiness boost, but reduces consciousness permanently.
  • Furniture can now be art engraved.
  • New floors: gold tile, sterile tile, cream carpet, dark gray carpet.
  • Game start now has a “select random landing site” button if you don’t want to choose.
  • Improvements to trade interface: better layout, expands vertically to use all screen space, increment/decrement buttons and launch/drop all buttons added.
  • Added ‘open’ designator for opening cryptosleep caskets, graves, sarcophagi, and other containers.
  • Manhunter pack incident can use animals besides wargs.
  • Commands are shown if there is at least 1 selected object with this command, instead of requiring all selected things be able to accept the command.
  • Dazed broken pawns will now randomly strip off clothes and drop things.
  • New graphics for squirrel and warg.
  • New graphics for research bench and other buildings.
  • Unskilled or injured growers can fail at harvesting, destroying the harvest for one plant
  • A bunch of new music from Alistair Lindsay.
  • Carrying capacity is now a stat that can change for body size and manipulation capacity.
  • Siegers will never be sent with only melee weapons (too exploitable).
  • Sappers now avoid mining through high-health ores and barriers.
  • Rebalanced crop yields and harvesting challenges so crops require a bit more space.
  • Game will auto-reset mods config on startup crash to try to recover.
  • Tons and tons of bugfixes and other adjustments, refactorings, balancings and tunings.

Hotfixed to Alpha11c (Update: Alpha11d)

Posted July 22nd, 2015 by Tynan Sylvester

Alpha11c is a very small hotfix to Alpha11b that fixes a few serious bugs. All save games and mods should still be compatible.

Update: Now to Alpha11d. This is the same as Alpha11c, but the save game location will be correct on Macs. (I originally built Alpha11c against a slightly old version of Unity from before they changed the save game path).

There will not be a new email sent. You can download using your previous link from your last email. Your personal download link is permanent and always has the latest version. If you need help getting your link, please go to ludeon.com/support.


  • Mitigated a game-killing bug caused by corrupted pawns. The corrupted pawn will now be destroyed instead of causing broken saves and game crashes. I’m still tracing the root cause of this so I can make the game not generate corrupted pawns in the first place.
  • Fixed a stuck-pawn bug caused by wardens trying to recruit downed prisoners and immediately ending their job, over and over.
  • Fixed prisoner config resetting at inappropriate times.
  • Fixed floor smoothing speed being determined by mining skill (it’s now construction).
  • Fixed repeated EMP damage canceling stuns in progress.

Quick update upcoming developments

Posted July 22nd, 2015 by Tynan Sylvester

Hey everyone, hope summer treats you well. So here’s the state of development now:

First, players found some rare but game-killing bugs in Alpha 11b. As in, they can actually kill your save game and make it unloadable. I’ll probably be releasing a small, non-essential hotfix to Alpha11 to fix these. This will be a minimal fix with no new content or changes to compatibility.

Second, Alpha 12’s key feature will be animal husbandry and related features. It’s an ambitious update: new animals, animal mating, reproduction, egg laying, species life stages with different labels, appearances, and statistics, perhaps animal training, attack animals, and so on. Piotr is also working on some other juicy features: new varieties of one-use ancient artifacts for psychic attacks and control, a new room stats system so pawns get happier when they have impressive rooms and heal better in sterile hospitals, and passive ‘facility’ buildings that enhance the function of other nearby buildings.

So I think Alpha 12 will be an important update, but it will take some time. It might not be finished before the end of August, in which case it’ll have to wait until 2016 (since I’m taking a break starting in September). I considered just releasing what we have but I really don’t want to release animal husbandry in a half-done state. I want you to experience the glory of it all at once.

In general everything’s been going great, and work is progressing rapidly. Currently I, Piotr, Rhopunzel, and Al are all working on RimWorld, so great new stuff is getting slammed in every day. It’s fun!

And now, a picture of wargs and Yorkies next to a pile of corpses.



Alpha11b released

Posted July 4th, 2015 by Tynan Sylvester

I’ve just released RimWorld Alpha11b! This is a fix-and-adjust build without crazy new features. You can still load saves from Alpha 11 (though they will report some errors on loading and have a few minor issues around load time, they should play fine in the long term).

Mods might become incompatible. I’ve tried to keep the API the same as it was before, but a few places have necessarily changed. Also, since the DLL was recompiled, the ABI might not be identical. This means the functions and variable names are the same, but the compiler might have changed the way the bits and bytes are passed around, causing code compiled against the old DLL to not work properly when it tries to talk to the new DLL. This means:

  • Simple mods (especially those which are purely XML data, images, and sounds without any code) should still work without any changes.
  • Mods with code might work without changes, but there’s a good chance they’ll need to be recompiled against the new DLL.
  • A few mods will actually need to have code changed if they touch parts of the API that I changed.

If you own the game, you can get the new version by re-downloading from the link you used before (it is a permanent link and always has the newest version). Anyone still having trouble should start at the support page. A new email will not be sent for this update.

Full change list:

  • Colonists will now try to avoid pathing outside their allowed area.
  • Open doors equalize temperature faster.
  • Much, much smarter sapper escort AI.
  • Sapper now avoid mining high-health ore while finding tunnelling paths.
  • Reorganized and clean up options menu and graphics settings.
  • Mods config page shows load order of mods.
  • Toxic fallout kills plants much more slowly.
  • Enemies (especially wargs) now ignore unpowered unmanned turrets and mortars.
  • We no longer allow buying back prisoners you just sold as a way to insta-recruit anyone.
  • Can no longer sell rotten items.
  • Treatment result is now indicated with a text mote, not a global message.
  • Adjusted a bunch of sound volumes.
  • Fixed pirate merchants only bringing slaves when population is high. This should be reversed.
  • Reworked how slave prices are calculated so they take injuries, capacities, and skills into account better.
  • Colonists now harvest planted trees on their own.
  • Optimizations to grower work scan algorithms.
  • Cleanup on main menu background image.
  • Smelt slag recipe can use do until you have X.
  • Siegers can never use melee weapons (too exploitable).
  • New sound: warg voices.
  • New sound: treatment.
  • New sound: medicine used successfully.
  • Player-created backstories and translations have been updated.
  • About 150-200 bugfixes – some big, some small.

Steam release moved to 2016

Posted July 3rd, 2015 by Tynan Sylvester

So after some great conversations about the Steam release and some more thought, I’ve decided to hold off on the Steam release until next year.

Originally, I wanted to get the Steam release out so you would all have access to Steam features and automatic updates while I was on break. To alleviate concerns about me not being around for my break, I thought I’d write a blog post describing the exact state of the game and where development was heading. The idea was that anyone could read it and decide for themselves whether they wanted to buy the game or not.

However, on further discussion it seems like a risk. These days, people assume a lot about a developer and their process very quickly, and a lot of it can be negative. A lot of people have been burned. So no matter how much I communicate, a lot of those messages won’t be read, understood, or even believed. I hope I’ve built up some trust among RimWorld players by my actions in the past – but with a Steam release come a lot of new players who don’t know me from a hole in the wall. My fear is that misunderstandings and accusations around me taking a break soon after release would taint what I think will be an otherwise strong release on Steam.

The benefit of pushing to Steam now doesn’t seem worth it. Steam Workshop is nice, but a lot of people don’t use it even when they have the option. Automatic updates are cool, but there’s not much point when the game isn’t being updated because the developer is on break. We already have a well-working release system that’s served us all well for almost two years. So there’s just no great hurry there that outweighs the risks.

I’m sorry for the confusion on this and I hope this isn’t letting anyone down too much. Of course, the game itself will be the same either way (in fact, we might get more content out in the near term because of time saved from Steam release hassles). I also really appreciate everyone who took the time to write out a full set of thoughts on this topic. You’re not just giving me two-line low-effort responses; you’re giving me entire essays, and it’s really useful. I am listening and learning from you guys all the time.

In other news, Piotr Walczak, Polish coding prodigy has rejoined me after his school year. You may remember him as the guy who wrote the original code for the health system last summer. Having him around should help increase development speed.

Alpha11b is approaching final testing. It’s a massive bugfixing, tuning, and adjusting release, with hundreds of bugfixes and many balance changes and other small improvements. It’s also compatible with Alpha 11 saves! So look for that to come out soon.

On the upcoming Steam release

Posted July 1st, 2015 by Tynan Sylvester

The news that people have been asking me about for years is finally here! I’m planning on releasing RimWorld on Steam Early Access around the end of July or early August.

(Edit: Having considered the feedback so far, there’s a good chance I may release the game on Steam as a non-Early Access finished game. Read below for why. Nothing of substance would be different from how it’s described here – it’s just a labeling/PR issue.)

At that time, the key distributor will be set up to give out Steam keys to qualifying existing buyers (currently it only gives your non-Steam download links). I’ll try to get the keys up at the same time as the Steam release, but be warned that there might be a day or so of delay. In either case, the content will be the same on and off Steam.

Steam Workshop will be supported from day one of the Steam release, so it’ll be extremely easy to subscribe to mods. In fact I’m a little worried that people won’t come to our thriving mods forum any more! But I think it’ll be okay. A community this awesome is about more than just getting the mods.

In the run-up to the Steam release, I’ve been focusing my efforts on perfecting what there is of RimWorld rather than biting off chunks of new content. If you read my changelog you already know that I’ve been obsessively bugfixing for a month now. As I mentioned in the Alpha 11 release video, I’m pretty satisfied with the shape of the game. Up until Alpha 11, there were always big holes in the design. Back in the days of yore it was the lack of real hauling and stockpiling (resources were stored in hammerspace, like StarCraft II). Then it was the monotony of a single enemy type with a single strategy. Then the monotony of a single biome. As each piece was added, it filled in a missing piece in the design. The last hole was the one represented by the all-powerful killbox strategy which funneled dumb enemies into a single turret-lined room. Alpha 11’s new sapper strategy solved that.

Now, for the first time, I look at the design and I don’t see gaping holes that need to be filled. Of course, there are still countless things that could be added to the game. I have a document listing hundreds of them. But they all feel optional to me. What’s there is a rounded, integrated design. In my mind the design always used to look like an irregular lump of Swiss cheese; now it’s more-or-less rounded and more-or-less smooth.

So is it done? I’ve thought a lot about what it means to call a game “done”. Ten years ago, a game was done when it was printed to disc. But with digital distribution, we never lose the ability to keep changing a game. So when is a game done? Is it just when you stop adding things? No, because a game can be abandoned without being finished. Is it when there’s nothing else that could be added? That’s not reasonable; I could work on RimWorld for 50 years and never satisfy that. In the end, I think that a game is done when promises have been fulfilled, and there aren’t holes in the design. And we’re reached that point, so RimWorld is done.

That said, just because RimWorld is done doesn’t necessarily mean I’m done with it.

I like working on the game, you all like playing it, and it’s profitable. So I probably will add more content to the game. In the meantime, though, I think it’s time for a bit of a break. I’ve been working on RimWorld and its prototypes for going on three years straight now, and my hours are usually pretty long. I’m starting to feel a bit of burnout. I often seem to develop this dull ache behind the eyes after a couple hours of work. I have trouble concentrating for the lengths of time that used to be normal for me. For that reason – and just because I believe in having a life that isn’t all work – I’m taking some time off from full-time RimWorld development starting in September. Currently it’s looking like it’ll be about six months. I’ll still be around to interact, but I won’t be developing constantly like I have been.

I can’t say exactly what will happen when I return. I might just take the feedback from the Early Access release, integrate it and release RimWorld 1.0 without major new features. Or, I might continue developing the game for years. As I said, I like working on RimWorld, but I’ve also learned that the future is very uncertain and it’s a bad idea to make promises you’re not sure you can keep. That’s part of why I’m telling you about my break now, before the big Steam release. In any case, as always, I encourage people to only make buying decisions about the game based on what it is today. Please don’t ever buy any game – including mine – based on a guess at what it might some day become. Hype trains crash a lot.

So – that’s all the news! I also want to say thank you. There are a lot of scary stories about indie development, and back when I quit Irrational I wasn’t looking forward to facing the poverty and vicious online hatred I kept hearing about. Thankfully, this whole process has actually turned out to be great all around. You’re make this community fun and interesting to interact with. This is an awesome job and I very much appreciate you in giving it to me.

New trailer released

Posted June 13th, 2015 by Tynan Sylvester

I’ve just released a new RimWorld trailer! The format is the same as the old one, but all the content has been updated to the new hotness. Enjoy.

RimWorld Alpha 11 – Sappers and Traps released

Posted June 10th, 2015 by Tynan Sylvester

It’s here! This update includes clever new AI strategies including sappers who blast and dig around your defences and raiders who burn crops. I’ve also added a number of incidents, including several long-term atmospheric conditions like volcanic winter and toxic fallout. There is also an array of new traps for players to use, dozens of other new features and hundreds of fixes and small improvements. A full change list is at the end of this post. If you wish, you can also read my day-to-day work log here.

If you own the game, you can get the new version by re-downloading from the link you used before (it is a permanent link and always has the newest version). You should also get an update email from us. Anyone still having trouble should start at this thread. There may be a delay of some hours before your download count resets or your email arrives.

Also note that this build will not load old savegames or old worlds, so please don’t try to load these in the new version. They’ll probably just crash the game.

Change list:


  • Added new raid type: sappers.
  • Sappers attempt to dig or blast their way around your hardest defensive point. The circumvent ‘killbox’-like strategies.
  • Enemies now flee things that are about to explode
  • Enemies remember trap positions that their faction has encountered before, and avoid them.
  • Raiders opportunistically ignite crops on fire.
  • Pawns can now do ‘job override’ checks to see if a new job should start before ending their current job. These are now used liberally to have pawns respond faster and more intelligently to changing conditions (especially in combat).
  • Pawns check for job override when taking damage. It will no longer be possible to bug out the centipede enemy and kill him at close range while he tries to take a firing position.
  • Enemies no longer take unpowered player turrets as primary targets.
  • Pawns choose sky-gaze, wander, eating and other positions by traversing the region graphic instead of by random coordinate scattering, which solves problems with them taking long paths around long walls.


  • Added deadfall trap: A simple rearmable trap that falls on enemies and damages them.
  • Added IED trap: An artillery shell connected to a trigger that detonates after a short delay.
  • Added incendiary IED trap: Like IED, but sets fires.

New incidents

  • New incident: Toxic fallout. A toxic cloud that lasts for days or weeks. It kills plants, rots food, and slowly poisons people outside. Toxic buildup in characters leads to vomiting, dementia, and eventually death.
  • New incident: Volcanic winter. Lasts weeks or months and significantly reduces temperatures and light levels, leading to poorer harvests.
  • New incident: Manhunter pack. A pack of deadly wargs arrives and stalks the local area for a while before moving on. Fight them or hide inside from them.
  • New incident: Chased refugee. A refugee radios and offers to join the colony if you’ll fight the raiders on his tail.
  • New incident: Psychic soothe. The opposite of a psychic drone.

Allowed areas

  • Assign colonists to allowed areas.
  • Every item and location outside the allowed area is considered forbidden.

Storyteller changes

  • Storytellers will never entirely disallow events because of population.
  • Randy’s event chances are affected by population (somewhat).
  • Re-tuned storyteller population intent based on new output tables for smoother population gain with higher maximum and better recovery at small populations

Ice sheet

  • Ice sheet biome is now playable (though perhaps not survivable).


  • Added strip designator to reduce stripping micromanagement.
  • You can toggle allowing sowing in a growing zone.
  • Doors can be held open.
  • Door locking is now door forbidding (it’s clearer).
  • Added copy/paste functionality for storage zone/building settings.
  • World data now saves into map file to prevent game state confusion with multiple saves on one world.
  • Added new joy activity: build snowman.
  • You can now remove floors to reveal the terrain underneath.
  • You can now perform surgery on guests. Violating surgery will anger their faction.
  • Guests are smarter and no longer walk out of the colony bleeding.
  • Added new hairs donated by Shinzy.
  • Slave trader changed to pirate merchant, can still show up to buy slaves even when your population is high (though they may not carry any).
  • Hundreds more bugfixes, tuning changes, optimizations, and other small improvements.