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.

43 Responses to “RimWorld Alpha 11 – Sappers and Traps released”

  1. Adamiks

    Alleluja!!! Alpha 10! Yey!

  2. It’s 11 this time!

  3. Anthony

    I literally just finished downloading Alpha 10 and you just sent out 11! lol wow, very cool!! I love the idea of adding more to random events. Adds a lot more fun to each game!

  4. Jepo

    Amazing! I’ve been watching the daily changelog and waiting with incredible anticipation for this drop.

  5. ImpulsiveZombie

    I like to imagine that the soothing drone just appears on comm frequencies and does nothing but play smooth jazz.

  6. Daniel Siegmann

    Looks good. But how come the man eating dogs leave incapacitated people lying around? I would expect them to rip those people to shreds and devour them.

  7. Trako

    Do you want to build a snowman? It doesn’t have to be a snowman.

  8. STOP! I want to capture, domesticate, and train the wargs to do my bidding. You have to make this happen. I appreciate the fact we can create “art”, but I just do use that…at all.

    But I would love to be able to create a kennel and release these mutts on my enemies. Please, Tynan, you gotta make this happen. This would be like a coding ode to Stronghold.

  9. Kij421

    I agree with Thomas W. I just finished downloading, but I think we should totally be able to tame wargs and use them in our defenses or in hunting parties.

  10. ORCACommander

    Counting the seconds till someone names pirate merchant back to slave trader.

  11. I just changed it to pirate merchant because it was merged with the weapons trader, and also carries other ‘black market’ items. So you could call it a slave trader but it’d be a misnomer.

  12. LOKI2030

    im wondering if youre going to add some type of economical system for people who just wander into your colony visiting? trading stalls, taverns and the sort; a market place for them basically. im trying to figure out if there is any purpose to them other then just visiting a colony. i see them come to my colony all the time and then just sleep outdoors then die from exposure and such.

  13. Dantronix

    Tynan, once again, you are a bad ass. Thanks for all the hard work! I adore this game. Simple suggestion/request: Can you combine area/zone tools so that one tool places zones but also deletes them when holding down shift or alt or something?

  14. Tyrion

    Love this imaginary world you created. It might be the best “life” simulator out there. For that reason I hope you will never quit on it. The possibilities for Rimworld are endless. Im just worried that I heard “Im done with this” tone in your voice..

  15. Listen1

    Alot of people seem worried about the last comment, that you are happy with game.

    You danm sure you should be happy! You implemented areas that will change the whole game. The game is getting great shape, since i’m following it since alpha 2, i’m getting more and more impressed.

    We are almost getting a stable enough version for steam release, which will grow our modding community even larger, and bring the game to the whole world.

    If Tynan decides that the game is ready, and he will start making a new project, we have an awesome modding community that will fill us with marvelous mods.

  16. Etherlord

    I love these creepy things like making an armchair from human leather, but I don’t think it should be a default option when I don’t have human leather anyway. 🙂

    Also, at some point you renamed “metal” to “steel”. It somehow makes sense for construction, but not for electric wires. I think you should either implement various metals and alloys, or you should rename it back to “metal” or “metals”, as when you use the material it gets refactored anyway, so it should be obvious you’re not building a structure from a single metal element.

    One more thing – let us build underground power reactors, please! It’s hard (or impossible on current version?) to find geysers below mountains, and you can’t build ship nuclear generators below roofs. I’d love to create fortress unpenetrable by mortars.

  17. Guy

    That’s awesome, man! Thanks for your work, i’m already downloading it. You know, i really think to buy your game some day.

  18. Dr. Z

    Ice sheet takes its toll.

    That’s all I’m gonna say.

    And praise the squirrel.

  19. Monkey Marsden

    Challenge accepted !

  20. Monkey Marsden

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

    Challenge accepted !

    (sorry for XHTML messup)

  21. Megfir

    Inspiring work, Tynan, thank you very much.

    For me the relationship module is something I would want to see fleshed out still as a major feature. To get the colonists forming emotional relationships, which would make their deaths even more devastating for the player. 😀

    Thank you again!

  22. Brin

    I’m running into a problem digging into a mountain. They won’t dig into Slate several spaces back. The game says it is Forbidden, but nothing I do changes that. It isn’t a wall, so it can be claimed or deconstructed. I shot my way past the first block, but behind that is the same problem. They can dig slate to the left or right, but not beyond that row.

  23. Brin – is it outside their allowed area?

  24. Matysier

    Ice sheet is awesome! Cassandra got angry with me and sent wargs, toxic fallout and two raids back to back, all in -75 degrees weather. I love it, finally my colonists are struggling to survive.

    The harsh life made them a little too empathic though: they go and feed incapacitated raiders. I noticed after breaking siege that my warden is carrying a meal across entire map to some unfortunate fellow I left to die in the snow. Quite silly :]

    No other significant bugs detected. Nice release.

  25. Loki Reinhart

    Hey Tynan !
    I’ve finally bought your game and i notice something . . .
    Some of my guys just spend a crazy amont of time praying every days . . .
    Is it normal . . . ?
    It is especially annoying when they have things to do and they just stop working to go praying . . .

  26. Loki – you should give them other joy sources. They’re tolerant of praying so it’s not affecting them fast so they need to spend a long time on it. Give them a variety of joy sources.

  27. Etherlord

    Opened doors don’t propagate heat.

  28. Pyro

    You should add instrument actually. They could contribute to joy if good musicians play.

    New trait fitting this could be Tonedeaf and the opposite to being tonedeaf would be Tonerich or something alike.

    The Tonedeaf trait basically makes them horrible singers/musicians and makes them much slower at playing instruments and bring little to no joy whilst the oposite happen to Tonerich people.

    Coul add maybe a Guitar, Microphone.

    Karaoke. Yes. Just yes. Karaoke is best for the drunkards!

  29. Dogthinker

    Opened doors do propagate heat in my colony. It’s not as fast as I remember from my last game (alpha 9), but if I leave the doors open on my new ice sheet colony, all the rooms steadily drop to sub-zero temperatures over the next few minutes.

    I think you’re expected to use the new air ducts for heat balancing, although that’s not instant either.

  30. Arrowcrest

    Every single one of the Misc changes is something that I have been dying to see (well, with the exception of the work under the hood, like with the map data).

    Either you are my telepathic mind twin, or one of the most community responsive devs I have ever come across.

    Bravo; +5 internet points

  31. SpartanEcho

    This game is really turning into something amazing. The only thing i still hope for is that you implement water that is needed for hygiene and cooking

  32. Joseph

    Musicality might fall under “Artistic”, complemented by a separate starter career. New traits “Tone-deaf” and “Musically Inclined”. Add items such as musical instruments and phonographs and radios, and allow joy sources “sing”, “play instrument”, and “listen to music” (both live and recorded). (Live music joy source would be the first where one colonist depends on another for it.) Additional artist bench tasks include “record music” and “create instrument” — might be new specialized benches — which end up with quality-rated recordings and instruments which can be sold.

    Maybe also joy source “dance to music” (live and recorded). Good way to give prisoners and visitors extra bonus on trying to recruit?

    +1 on Karaoke — drunkards in range get extra joy for singing and for listening. (Treat as temporary “Tone-deaf”?) Microphone and speaker (“PA system”?) would increase audible ranges of music being played. Being in hearing range of bad singing/music gives negative mood to the “Musically Inclined”. Oh, this could be quite interesting ….

    Heh. “PA speaker” as buildable tile, must be powered, and when hooked to a playback source, can play recorded music which soothes or drives away or attracts animals or raiders. “Attack of the Killer Tomatoes” anyone? 😀

  33. Grenadier33

    Rimworld goes to eleven!

  34. GenStone

    So, I had to bring the game from another computer, because it had to be sold, and I dont know how to update it from there…. Its at Build 0.10.783, Can someone help me with this?

  35. Ryan Evans

    Ever since the Biome update i have been waiting to play on an ice sheet, thank you. It will be interesting to see how this goes haha.

  36. Jack Cap

    Hey Tynan, just wondering, was the event-stopping bug (switching to/from randy) fixed?

  37. Thank you everyone 🙂

    Jack: Yes it was.

  38. Jack Cap

    Thanks for the game Tynan 🙂

  39. Alex

    Tynan, you said you were almost satisfied with the game. Which is awesome and terrifying at the same time! One thing I’ve wanted for a while are some “Attempt Fix” surgery’s. For example a lesser one would be if say, a colonists heart was at like 70% efficiency for some reason. Instead of having to do a transplant you could send a surgeon in to attempt to repair the damage, with a failure percentage equal to the damage done to the organ, so for this one 30%. Or for a more complex one, if both of a colonists kidney’s are failing, then perhaps having surgeons “merge” the kidneys, using healthy parts from one to fix the other. This is the future after all. Also maybe some moral consequences to attempting to save a patients life. Like if one patient goes through several extreme surgery’s, such as limb and organ replacement, other colonists begin to have doubts about preserving the humanity of the patient and the colony. It would make the player consider how much his colonists mean to the colony, whether they should live half a life or none at all. I realize what I’m asking is a major undertaking, but if any one of these made it into the game I’d be your biggest fan!

    Also – had the game since the alpha release – LOVE the progress, especially (yes) the medical system! Great work Tynan! Keep it up!

  40. Jonathon

    Hey Tynan,

    First off, love the game and the new update.

    But with the addition of being able to play on the ice sheet it brings up some features that would be really useful (plus a new block)

    What I have found to be lacking is any display of insulating value (thermal conductivity or R value) of structural materials.

    ie, silver looses more heat then gold, gold looses more than steel, which looses more than stone, which is more than wood, which is more than air(non circulating).

    Having this value listed (or knowing they are all the same) would dramatically affect how the building are designed.

    The additional structural material i would request is a composite (made out of fibers like cotton or devils strand, wood, concrete, steel) to make a highly insulation wall with little structural integrity (so it is not a wonder material that you use for everything), but more likely in the high arctic and the freezers in the jungles.

    Every other request I would have made you have incorporated your own unique methods of dealing with them, and I look forward to what you add next.

    Have a great day,


  41. RulerBrendan

    What this game could use is an area prioritize option. I have some steel that needs to be mined, but when I prioritize it, they mine for 2 seconds then go do something else. That one block isn’t enough to finish a door, so it’s somewhat annoying. So if you could at least consider that, that would be great 😀

  42. Etherlord

    Thanks for your response. I stand corrected – opened doors propagate heat – but I think they do it much slower than closed doors that are opened only during passage of colonists. I’ll check later.

  43. Conor

    I don’t have enough money for this game, but i have been watching a lot of videos about it on YouTube. RimWorld looks like its so much fun! Keep up the good work Tynan!