YMMV / RimWorld

• Alt-itis:
  • Ideology offers a dizzying array of potential ways of life, some of which synergise with each other perfectly. It's very tempting to make several Ideoligions just to try out all the different options for Specialists, rituals, aesthetic styles and craftable items.
  • Biotech likewise gives the player nigh-limitless options for making their own Xenotypes and mixing a colony's population to make the perfect combination of individual pawns with their own strengths and weaknesses. The player may even choose to try a colony with only one organic pawn and an army of Mechanoids as a major Self-Imposed Challenge.
• Come for the Game, Stay for the Mods: The game is most well-known for being extremely mod-friendly, and has a very extensive list of player-made mods in the Steam Workshop; it's rare to find a longtime player who doesn't play with many mods added to the game, whether that be extensive overhauls to the gameplay or just for some small quality-of-life simplifications, and updates/DLC frequently add mod content to the official game.
• Complacent Gaming Syndrome:
  • Whether by design from the start or simply by pressure from the ever-escalating hordes of enemies, most long-term colonies have relied on killboxes (enclosed spaces designed to funnel enemies into exposed positions where they can be easily dealt with by massed turrets) to defend themselves. Alternate defensive strategies are a common request by fans. Since the release of Alpha 11, sappers and improvements in AI combat priorities have made killboxes less effective, though they are still quite potent in most situations. In addition, pirates will set up mortars and bomb your colony from outside the killbox's range, and angry tribal hordes can simply charge right through the killbox and overwhelm it with raw numbers. Finally, more advanced enemies can bypass your defences entirely by transport podding directly into your base.
  • Mountain-based fortresses are virtually impregnable, as the thick stone walls are hard to tunnel through and tiles with mountain roofs can't be damaged by mortars. Insect infestations were introduced to make mountain fortresses less dominant, but can be made manageable with proper planning. Insect meat can even be turned into kibble and fed to animals, making it free food.
• Demonic Spiders:
  • Centipedes with inferno cannons. Just one is enough to massacre an entire colony. Thankfully, these were nerfed severely.
  • Pirates with rocket launchers. Rockets from launchers cause massive explosions and destruction, so naturally they are one of the most dangerous enemies in the game. Fortunately, they don't wear expensive and durable armor gears, so killing them is easier than mechanoids or elite pirates.
  • Thrumbos are huge, peaceful, and generally inoffensive creatures... but if attacked or go manhunter, they become unstoppable killing machines that can wipe out entire colonies in minutes.
  • Manhunter packs. Late-game manhunter packs come in vast hordes that can tear through walls and clog a killbox with hundreds of corpses and they can be made up of huge numbers of tiny animals like rats, squirrels, or hares. These can be especially dangerous early in a colony's life because they're small, hard to hit, and come in substantially larger numbers, and while they do little damage and have no armor-piercing that won't matter if you don't have armor yet. Treating all the scratch and bite wounds you're likely to get costs a large amount of medical supplies, can lead to deadly infections, and may cause scars or missing eyes or fingers. Boomalopes and boomrats, which explode when killed, are also possible. If you don't have a lot of ranged defenses by this point you can say goodbye to your crops, and potentially your whole colony if it's still made of flammable materials like wood or steel. Or they can be include modded animals, which can be devastating depending on what you've installed.
  • Insect hives in general, which come with the bonus of actual "spiders." They'll randomly spawn in any tile under a mountain roof and will show up with dozens of tough or swarming insects who will aggressively attack anyone who gets too close, and can absolutely ruin an unprepared mountain base.
  • Ideology introduced mechanoid siege units called Termites. While not overly difficult to kill, their main gun has above-average range and deals such ludicrous damage to structures that a single shot instantly obliterates any walls and turrets in its blast zone. The gun is so strong that not even multilayered walls provide any protection, nor does the material your walls are made of matter at all - reinforced plasteel goes down as quickly as flimsy wood. Termites also tend to show up in packs, and given any colony's forced reliance on static defenses, can take away the player's only advantage in battle in an instant. It took modders less than a day following the expansion's release to nerf the Termite to more manageable levels. Termites were so strong that siege raids in general were made less common (they ended up being more likely than originally intended), with termites also taking massive nerfs in particular (For example, they only do X2 damage against walls as opposed to their original X4, and their range is slightly lower).
• Epileptic Trees: Due to Biotech disproving the theory that all DLCs for Rimworld would spell out the name of the game, many players speculate that the DLC might have originally had a name that started with an "M" which was changed due to rising scope. The supporting evidence for this speculation is the fact that the DLC was confirmed by Word of God to be originally much smaller in scale, meaning that it might have featured only mechanoid content originally and been named something like "Mechanoid" or "Mechanitor". Due to the DLC's teaser art (featuring also a baby), some others have speculated the DLC could have been named "Motherhood". The added children and genetic content might have necessitated a name change and a break from the original naming convention.
• Fan Nickname:
  • "Hats," for colonists who are useless or undesirable. Since any animal can be butchered for meat and skin, including humans, a popular joke is that even the most worthless colonists can still be made useful by turning them into clothing like hats.
  • Mostly due to the once-prevailing theory that the DLC packs would've spelt out Rimworld getting debunked with the Biotech DLC, some have taken to call the game Ribworld to varying degrees of seriousness.
• Game-Breaker:
  • Killboxes, infamously so. They consist of a wide-open area at the entrance of a base filled with traps, firing points and turrets, with a tight passage funnelling enemies in. Even large raiding parties with numerical and armament superiority can be quickly decimated in short order by Death In All Directions with nowhere to take cover. A well-built Killbox can easily neutralise any threat posed by raiders, and some players still refuse to build them because they suck the challenge out of the game, even after sappers have been introduced and the strategy is not the dominant force it used to be.
  • Smokeleaf joints are an easy way to make lots of money if you have a colonist with "4" or more in their growing skill and sufficient space to sow smokeleaf plants. The joints themselves can be very quickly made from harvested smokeleaf in a tiny crafting spot, with no minimum skill or technological level required (tribes with neolithic tech from the "Tribal Start" scenario can do this from the beginning), their weight is ridiculously low, and they stack at 400, so you can carry large amounts when forming a caravan. (Make sure to set a smart drug policy before doing this, or your colonists will binge on your weed stock, lose all productivity, and eventually become addicted.)
  • Royalty added Psycasting, and even the weakest one can save a colony. Stun can shut down a rocket raider for a bit, and the upper skill Berserk can make him Kill his own buddies. Skip can reposition any target within eyesight, and place a sniper in the middle of a killbox, or in range of a melee brawler. Wall Raise and Chunk Skip are instant cover, and Vertigo can make an entire group of raiders puke their guts up non-stop.
• Good Bad Bugs:
  • Animals such as squirrels and iguanas (among others) can get into your alcohol stash and drink the beer there.
  • Before there was a hard cap of 100 put on it, quests where new colonists would join you if you protect them from Manhunting animals could give you such things as hundreds of foxes or dogs, or even literal thousands of squirrels.
• The Inverse Law of Fandom Levity: The many atrocities you can commit are more likely to be Played for Laughs in memes, while in game, they're considered as horrible as they should be unless you specifically fill your colony with psychopaths.
• Memetic Mutation:
  • "But me X", with X being an occupation that one is not very good at or is pointless ^ExplanationA joke originated from this fan comic◊ in which a lone pirate attacks a worthless colony just because he is a pirate
  • Happy birthday! ^ExplanationOnce a person reaches a certain age, after that point any time they have a birthday, there's a chance for them to gain an "old age" flaw like a bad back, cataracts, or frailty. Cue the fans declaring that birthday presents in Rimworld involve the Storytellers gifting them with debilitating medical conditions.
  • Ate without table ^ExplanationEating without table will give colonists a mood debuff. This can lead to weird situations like "My colonist went berserk, and his final straw was 'Ate without table!'". Thanks to certain glitchiness with tables this can happen even if you have enough tables around, and it's likely to be The Last Straw for a mental breakdown thanks to its repetitiveness. This has also lead to fans treating forcing a pawn to eat without a table to be the worst thing you can do to them. There's even a meme mod that makes colonists instantly die if they eat without a table!
  • In general, jokes about "space cannibalism" and "human leather couches" are rife in the fandom, precisely because they're so horrible. "r/SpaceCannibalism" is even the name of the Rimworld-related memes' subreddit.
• Mis-blamed: According to the official FAQ, Ludeon has been accused of stealing content from mods and basing their expansions around it, but any similarities is coincidental, since things like Psychic Powers, genetic engineering, and space vampires are common enough sci-fi tropes that it's not impossible for both Ludeon and modders to create game content based on them. Some of the expansions were also based on ideas that were already planned before the game even released.
• Paranoia Fuel: The Anomaly DLC introduced a hefty dose of this to the game, with things like invisible monsters that attack in packs, invisible monsters that hypnotize and abduct pawns (and can even open doors), sinkholes suddenly opening up in the middle of your base to disgorge hordes of monsters, or other monsters that are basically The Thing on steroids. That last one is a particularly nasty example. Called Metal Horrors, they start off as a nanite infection that can lay dormant for years, meaning it's entirely possible for a pawn you recruited half a decade ago to already have them. Once the infection takes hold, the host starts infecting other pawns through a multitude of ways, like the meals they cook, injuries they treat, or simply through physical/intimate contact. This way the entire colony can be infected before the first Metal Horror ever reveals itself, and once the first one pops out, leaving the host grievously wounded with hours to live at best, all other hidden Horrors reveal themselves at the same time, potentially wiping out the whole colony in one fell swoop. The infection can be detected via a surgical inspection, but if the doctor performing the surgery is themself infected, they'll lie about the test results and potentially infect any uninfected pawn in the process. Oh, and your pawns can get infected with Horrors through any cut or bleeding wound from any Anomaly entity. If you've experienced an outbreak like this even once, you'll never feel safe about... well, just about anything in the game again.
• Salvaged Gameplay Mechanic: Before 1.4, shelves were widely disliked since their only effects were to prevent items from decaying when left outside, and to prevent them from being visible to colonists (allowing for storage of corpses and unsightly items), so most players stuck to putting items on the floor. With 1.4, however, came widespread love for shelves, as they were buffed by making them capable of storing 3 items/stacks per tile, allowing for much more compact storage.
• Scrappy Mechanic:
  • Colonists who have "Incapable of X" traits, particularly ones that disable dumb labour like hauling and cleaning, or render them incapable of treating patients or putting out fire. One popular mod, "Pawns Are Capable," instead gives colonists a mood penalty for performing tasks that they would otherwise never do.
  • Infestations, mostly because they spawn underneath mountain tiles, meaning that even the smallest underground construction can end up spawning a horde of giant hostile insects.
  • In Beta 18, there were tornadoes that could randomly appear on the map at any time and wreck a good portion of your colony if you were unlucky. Unlike nearly every other event in the game, there was no good way to plan for or around one—you just had to ride it out and hope it doesn't knock out something critical. Players found tornadoes so frustratingly arbitrary that they were removed as a random event, though enemies may be able to call them down with a very rare single-use "Tornado Generator" super-weapon.
  • A Solar Flare shuts down every power-consuming item in your base for the better part of a day, which will knock a late-stage colony almost completely offline and can be outright fatal for a colony reliant on hydroponics or climate control. There's also nothing you can do to prevent or manage them short of never using electricity, disabling them entirely in the scenario editor at game's creation, or modding your game.
  • Short circuits will cause an explosion on a random piece of power conduit, with the size of the explosion based on the amount of battery power stored. This not only drains your batteries entirely but causes potentially enormous fires. While you can try to mitigate their effects, they can occur wherever there is a conduit. This issue actually results in wind turbines and solar generators not worth the effort, as their power output depending on daytime and weather (two factors the player has zero control on) makes them an unreliable source of electricity if not supplemented by batteries. The other power sources are as well less interesting to use in practice than they seem on paper, since their power output is constant regardless of external condition (beside solar flares) but they either require regular resources supply (Wood-fired generator, Chemfuel powered generator^note more efficient than the wood one, but requires transformed resources — and producing chemfuel requires electricity) or can only be placed on special spots which position depends on the map's random generation (Geothermal generator, Watermill generator^note only usable if the colony is built on a world tile featuring a river, which greatly limit its availability to begin with). As usual, mods exist to address the issue by introducing buildable circuit breakers or power grid management systems.
  • It's an unpleasant surprise for a lot of new players to learn steel walls are flammable and they need to use stone walls to fireproof their base. There are several highly-popular mods that specifically change steel walls to not be flammable.
  • The Toxic Fallout incident. The event itself is very annoying but manageable^note toxic weather that gradually sickens anyone who lets it build up too heavily, and kills any plants or animals caught in the open. The real problem is not what it does to your colony so much as what it does to the map. If you're unlucky or the Storyteller is feeling particularly sadistic, it can last up to fifteen days, more than enough time to render the entire map a barren wasteland devoid of any plant or animal life - including the trees you need for construction and power generation. The only way to avoid this is to design your colony around this eventuality from the ground up. Unsurprisingly, a mod to disable it completely is very popular on the Steam Workshop.
  • The Royalty expansion adds Paralytic Abasia, a health condition that causes total paralysis. That alone is annoying, but occasionally the game will drop a transport pod on you containing a refugee who already has it, who will automatically be added to your colony, whether you want them or not. Hope you like making hats.
  • Many players find the chance for some random furniture to become a "Masterwork" or "Legendary Masterwork" to be rather annoying, because it increases the colony's wealth value for no reason and beyond your control, making you more susceptible to stronger raids. This is especially true for shelves, since you end up needing to build a lot of them to store your stuff, and it's not like having a "Legendary" shelf lets you hold more stuff on it, making the masterwork status completely useless, if not detrimental. Unsurprisingly, there's a popular quality-of-life mod to change shelves to a "no quality" furniture type. Fortunately, the 1.5 update removed shelves from the "quality" furniture category.
  • Blight tends to be a particularly hated disaster, especially in the early game, due to the fact there's no way to guard against it, the game will just randomly decide to wipe out a large portion of your crops. This is made more frustrating due to the frequent Artificial Stupidity of the pawns when dealing with it; they will ignore any new blight that spread after the "cut blighted plants" order is given, allowing the blight to quickly re-spread to the new seedlings they immediately sow in the spot of the blighted plant they just cut down, and the pawns very frequently give up only partway through cutting the blight, allowing it to quickly spread further. Making "cut blighted plant" a priority for the pawns also doesn't help, as they will just cut that one specific plant and none of the others. Unsurprisingly, there are several mods that rework blight to be much less annoying.
• Self-Imposed Challenge:
  • In a game where Evil Pays Better is in full swing and it's hard to at least not be occasionally cruel, showing Video Game Caring Potential to your enemies or even following the Geneva Conventions is this.
  • Building a colony on Sea Ice means spending the whole game scrounging for resources. With almost no food source available until much later in the game, being a humanitarian is all but a necessity, and only some sparse slag chunks will give you any materials from your map.
  • Many of the Ideology memes and precept settings are blatantly harder to play than others, and a meme's impact rating doesn't necessarily correlate to its in-game difficulty. Whereas memes like Collectivist/Individualist are practically unnoticeable and others like Supremacist are almost purely beneficial, some like Blindsight^note blind pawns are crap at just about anything, something the meme's better doctors can't really compensate for, Tree Connection^note pawns go nuts if trees are harmed in any way, even by forces outside your control like a lightning-triggered wildfire, let alone logging to clear space for construction. The latter issue has been remedied by an update adding a feature which allows to unroot, move, and transplant trees without harming them, Flesh Purity^note no bionics and no drugs, not even alcohol, so no easy mood boosts for you or Transhumanist^note pawns have ridiculous demands for advanced biotechnological treatments that can't even be accessed until the midgame, and are extremely expensive and time-consuming once you have them pose a considerable challenge individually, and there's nothing prohibiting you from combining them as you see fit.
• That One Boss: Out of the numerous advanced Anomaly entities, the Fleshmass Heart is certainly among the most aggravating, not because it's particularly dangerous, but because of the negative impact it has on the game's performance. The thing gradually but quickly covers the entire map with itself, every single cell of it if you let it, which seems to hog an absurd amount of computing power that slows the game down to a crawl until the heart has been dealt with, a process that takes several in-game days at minimum. The meagre reward for defeating it just adds insult to injury.
• That One Disadvantage: Several traits have severe drawbacks that can make a colonist very difficult to deal with. This is intentional, as these drawbacks help add to the challenge and drama of the colony's story. As one of the loading tips notes, having a pawn who is worse than useless just adds to the tale.
  • "Incapable of X" traits, particularly where "X" is "dumb labour" or "violence". In the early game, being unable to haul useful items can slow down your colony's growth, and being one defender down when enemies attack can potentially spell trouble. As you gain more colonists, these traits become more manageable, but in the early game they can significantly crimp your growth.
  • Pyromaniac is considered the worst negative trait a colonist can have. They can't fight fires and have random mental breaks which cause them to go around setting fires: the consequences can range from some small fires, forcing your other colonists to clean up after them, to setting entire wooden structures on fire—or worse, your stockpile of explosives. They can also go on this break regardless of their mood. Several mods exist to change this, including one that makes Pyromania behave more like 1.1's update to Chemical Fascination listed below. Regardless, many players will instantly reject (or gleefully butcher) a pawn with Pyromaniac that shows up.
  • The "Volatile" trait gives a colonist a huge +15% higher mental break threshold, meaning they will be more susceptible to breaks. This is especially bad in the "Rich Explorer" start, where you start with a single colonist: if they suffer a mental break, your colony's growth will be stopped dead in its tracks for a long time. Depressive is also rough; instead of having a higher break threshold they get a permanent -12 to their mood. It's possible to get both these traits on the same pawn.
  • Chemical fascination causes colonists to occasionally binge on hard drugs like yayo and go-juice. While binging, they are uncontrollable, which can be very bad if you need them. At best, they might just develop a new addiction; at worst, they might overdose and die. This was changed in 1.1 to simply give a large mood penalty if they haven't done any drugs in a while, with the debuff getting lower and eventually turning into a buff as they do more and more drugs.
  • Gourmand is also pretty bad. Like Chemical Fascination and Pyromaniac, it has a chance to make the colonist stop working and go on a mental break even if they're not a break risk, in this case binging on food. At least they're not starting fires or overdosing, but they are still going to be out of commission for a while, and can cause other colonists to starve if they eat all of your food. This was given an upside in 1.1 as food binges are now the only mental break they can experience, meaning they will never go on any of the longer-lasting or more dangerous breaks, making it much more tolerable in a large colony with plenty of food. Making Gourmand worse, there's a long-standing bug that causes a pawn on a food binge to sometimes consider anything consumable to be food, leading to potential drug addictions and overdoses.
  • Alzheimer's and Dementia, which ruins the mental faculty of your colonist. Unlike some of the other medical afflictions in the game, there is no way to cure these conditions, even with the Ideology DLC's biosculpter pod. Your only real option is to manage the condition and care for the colonist until they can't properly function any more, unless you have access to the extremely rare healer mech serum.
  • Sickly means a colonist has a high chance to get a random illness. Unlike mental breaks, this can happen regardless of their mood, can't be prevented, wastes medicine, is always potentially fatal, and renders the colonist out of commission for a much longer period of time. It becomes even worse if a pawn also has the wimp trait. It's never a great idea to make a pawn work with the flu or malaria, but you can still do it if you need to. However the wimp trait causes a pawn to go into the downed state whenever they have even a tiny amount of pain, and all diseases will generally cause at least some amount of pain. The result is that a sickly wimp will just randomly get downed and need to be rescued every once in a while, and then be completely unable to do anything until they recover.
  • Slow Learner, which reduces learning speed on a pawn by 75% across the board, is an offence punishable by immediate hattification in the early game. It is far less of an issue later on, once you've built up your population and technology, and an otherwise slowly-learning colonist can be focused on cleaning or hauling. But early on, this can cripple your colony's growth - especially if they have a critical skill like Construction or Plants that requires certain skill levels to do tasks or not waste resources.
  • Body Purist, in which the pawn believes that their body should not be augmented with cybernetics or implants. They'll suffer mood penalties for any prosthetic part or implant. Early-game, this won't be much of a problem as you won't have any cybernetics to give them in the first place, but as the game progresses and your colonists risk taking injuries or you just want to upgrade them, the inability to give the Body Purist any bionic replacements can potentially cripple that colonist. This one can at least be alleviated with the Healer Mech Serum, which can regenerate lost body parts, but it will only heal one part at a time starting from the worst injury, which means that a Body Purist with multiple lost limbs will end up taking multiple serums, not to mention that you might want to keep said serums in case one of your colonists comes down with the dreaded Dementia or Alzheimer's. The other possibility is to use Biotech's and give them the Non-Senescent, Ageless, or Scarless genes, but these require spending rare archite capsules and hunting down the gene capsules, or finding a sanguophage and forcing them to implant their genes into the colonist, which will force you to deal with all the inconveniences of the xenotype.
• Underused Game Mechanic: Many players agree that more could be done involving the non-Empire factions and settlements that share the world as there are few ways to interact with them and, aside from trading, not much of a reason to do so. The only real function of settlements is to serve as better trade caravans that you have to seek out instead of coming to you, about on par with orbital traders but with greater variety. You can also attack them, but there's not much of a reward and it won't slow down raids.