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Rimworld, Dwarf Fortress, and procedurally generated story telling

Dwarf Fortress and Rimworld have been named story generators, a type of game in which fun does not come from reaching specific objectives but rather from seeing non-scripted stories play out from the actions of the player.

Henri Brouard, Blogger

October 9, 2019

11 Min Read

Dwarf Fortress is widely known for being an endless source of crazy stories. In the main mode, you spawn with a group of dwarfs in a randomly generated world and build a settlement to survive. The game is amazingly detailed, with every plant, each of your dwarf’s limb, and each of the hundreds of NPC’s in the game world being simulated with details. Since its release in 2006, players have used their game walkthrough to write multiple short stories filled with artworks. To interact with the game, you have to deal with an unintuitive and intricate UI system, highly abstract graphics, and no tutorial. Yet, the game still attracts thousands of players, and its official release on Steam is very much expected. Providing a similar game experience but more approachable, you have Rimworld. Rimworld is a western/sci-fi themed game with deep simulation mechanics that has sold more than a million copies and was the game with the highest reviews of 2018. The Adams brothers behind Dwarf Fortress, and Tynan Sylvester, creator of Rimworld call their game a story generator. A type of game in which fun does not come from reaching specific objectives but rather from seeing non-scripted stories play out from the actions of the player. Here I will try to present the main mechanics that make these game stories so appealing by focusing on Rimworld. 

  1. The three pillars: Set story framework, Semi-control and Event system

Set Story framework: Though Dwarf Fortress and Rimworld give players amazing freedom, (to an overwhelming point in the case of Dwarf Fortress) they also give a strong framework for the story to take place. When you start a new game, you pick a landing spot in a randomly generated world that already has a geography, history and people with set relationships. Then you choose three colonists with randomized traits and backstory. You may reroll the characters available to you, but you cannot change the character’s traits at ease. Once the game starts, the backstory of the characters, the personality of the NPCs, the animals, the events (after scenario pick), none of these are editable. As a result, every time you start a new game, a new set background is generated for you to make sure that the story will be different every time, even when the player wants to do the same things in the game.

NPC’s semi-control: The core mechanic of both games is about setting tasks to each colonist. Though its possible to force characters to work on specific tasks, most of the time the player just schedules each colonist daily work and their order of importance. That being said, how tasks are being performed or whether they are being performed at all is up to the colonists. Indeed, NPC’s personality, mood, physical wound etc. may alter the plan you have made for them in many ways. The psychological state of the character is indicated on each character mood menu: it is divided by positive and negative emotions, and varies according to the evolution of the story. The player cannot directly influence these emotions, and some of these emotions are unrelated to the player’s actions. For example, a colonist can be unsatisfied by his clothing appearance, the player then has to make different clothes until the colonist finally chooses the one that will make him happy. The way the player has limited control over the characters day to day activities and psychological state give NPCs a kind of autonomy and individuality.                        

Event system: Beyond the everyday routine of expanding your base and meeting with the needs of your colonists, events will regularly happen to shake things up in your colony. In Rimworld, it can be a mission to go somewhere into the world for a reward, people raiding or coming in to trade, two of your colonists falling in love etc. Most events are negative and they can give place to major crises that can affect your colonists in interesting ways. Thankfully, you can choose between 3 different “narrators”, that each pace and choose the events in a different way (Cassandra Classic, Phoebe Chillax and Randy Random).

2. The core narrative experience: Spiralling events

These three pillars create interesting stories through chain of events. Rimworld is a mechanic heavy game where events cause consequences that last in time, generating new events in connected chains. If a big enough event comes into play, it can cause rippling effects that if bad, can be devastating (and fun) for your colony. These chains of events are immensely satisfying on a player perspective because they strike a balance between player agency and unexpectedness. There is player agency because many of the events leading to spiralling effect are caused by the player. Rimworld is the game that you can finish and “win” if you are familiar with the mechanics. But there is also unexpectedness from the random events happening in the game, and from the spirals that emerge from the activation of connected chains of events.

Let’s take an example from personal experience in Rimworld:

Previous Events:

  • I have a group of seven colonists, my base is steadily developing 

  • Marius tamed a dog, and developed a relationship with him

  • After dating for many days, Steroid asked Harriet to marry him. She refused, which significantly deteriorated his mood

  • Nag has strong feelings about Marius


  • A signal appears on the world map. A man called Steven, claiming to be the ex-lover of Harriet says he is being captured, and begs to be rescued

  • I gather an expedition of four colonists to save him


  • While rescuing Steven, my colonists get ambushed, all of them are wounded

  • There is not enough food for the way back, the colonists starve

  • One colonist dies, the other colonists decide to eat his corpse for food

  • The dog, knowing about the death of his master, starts to go rampage in the base

  • The other colonists are heavily inflicted by the death of Marius, Steroid who got rejected by Harriet, and Nag who had feelings for Marius, have a mental breakdown

  • Its summer and a random heatwave hits the colony, we need to build coolers. Marius was a building specialist. With his death and the rest of my colonists wounded and psychologically shaken, the whole colony is at risk

On that occasion, my colony reached near collapse. But overall the roll-out of events felt amazing, leaving me surprised by how things turned out, but not frustrated like if things were out of hand. Spiralling events are never the same thanks to different story framework for each playthrough and the sheer diversity of random events that the game can offer.

The player should expect most of these spiralling effects to be negative. And in the case of Dwarf Fortress, the collapse of the player’s fortress is famously unavoidable. This is in part due to overpowered calamities that can randomly destroy the player’s colony, for example invasions or unbeatable monsters. But in many cases, while your fortress becomes more complex and your dwarves more interdependent, any small mistake can quickly spiral into disaster. Rather than being frustrating, the feeling of weakness makes the game evn more thrilling. It makes decisions feel more meaningful, and player may build stronger emotional ties with colonists that managed to survive disasters. As Dwarf Fortress motto goes, “losing is fun”. 

3. The graphics: Apophenia and ellipses

Finally, both games feature very simple graphics, and in the case of Dwarf Fortress, computer symbols and numbers. For Tynan Sylvester, far from being a flaw, simple graphics can be an asset for the narrative purpose of the game. In a blog post, he justifies it with the idea of Apophenia. Apophenia is defined as a human tendency to see and perceive connections and meaning between unrelated things. Typically, people may see animal shapes while looking at the clouds, or seeing faces on rocks and trees. This universal psychological trait can be a source of added meaning in video games. The faces, expressions and body language of the characters in Rimworld are mostly indiscernible, conversations and interactions are expressed with simple bubble pop-ups, and short sentences. The minimal game representation is suitable for players to make up events and stories in their head. This mind trick can only work effectively if players have spent a long time with their characters and have bonded with them emotionally. 

In a GDC conference, Sylvester uses the example of a doctor about to practice surgery on his wife. On the projected screenshot, you see a man standing next to someone lying on a bed. But as the face and the body expression is not shown, players can make up any kind of interaction from both characters. The interaction is enriched by the previous events in the game that characters “remembers”, whether its a previous failed surgery, a broken relationship or a happy marriage. 

During my playthrough, one of my characters got depressed from a failed marriage and other events. Instead of working, he would drink a beer and walk around aimlessly around the base, sometimes randomly lying down on the floor. All I could see what this 2D character moving around, and yet it really gave me the impression that he suffered a lot. So even though he was not an essential character among my colonists, I did everything to make him feel better, giving him long leisure time, giving him the best bedroom in the colony, giving him the best meals etc. 

A complementary tool used by the game are ellipses. In literature, an ellipse is a narrative device that omits a portion of the sequence of events, allowing the reader to fill in the gap. In video games, ellipsis can be used to make player progression more smooth and convenient. For example, traveling great distance of a world you already know can be quite boring. That's why many games have fast travel checkpoints, where you teleport through a short loading screen from one place to another. In the case of Rimworld, ellipses can be a powerful narrative tool. Time is not skipped, but the action is made invisible to the player. Not seeing the events taking place, or only seeing them through a short text can be felt in an even more dramatic way. For example, when you send colonists into the world on an expedition, once they are off your tile of the map, you cannot actually see them. They become a point progressing on the map. The fact that you cannot see your characters makes the expedition all the more thrilling. At any moment they can be ambushed, make strange encounters, or in my case run out of food and eat each other up. 

Also made invisible to the players are all the variation of mood and relationships happening in and between the colonists. If you don't take the time to check your colonists individual menus, these variations will be made visible in situations of crisis or status change, like if two colonists fall in love, or one colonist gets depressed. Because these mechanics are not directly on the screen UI, like with The Sims, it gives the impression that these changes are internal to the characters. 

To conclude

            Rimworld and Dwarf Fortress are games of a specific genre. But their narrative mechanics probably has something to teach to narrative driven games well beyond building sims. 

  1. Great non-scripted stories often take place at the intersection of player agency and unpredictability. Rimworld creates a great dynamic by giving a lot of options and freedom to the player thanks to the sheer number of things he can do; and then takes back some of that freedom by challenging the player with random events, or having unpredictable events as a result of players actions.

  2. Great storytelling can also emerge from limiting the control the player has over his characters. In Rimworld and Dwarf Fortress, game characters have a lot of “freedom” in the way they perform the tasks players set for them. Their emotions, stats and daily interactions with other characters and events shape their performance in a way that gives them autonomy over the player decisions, which can in turn create interesting and unexpected stories. 

  3. Finally these games narratives are made more meaningful thanks to the minimal way they are visually rendered. Events happening in Rimworld are made clear to the player, but the way the information is delivered gives space for narrative interpretation.

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