Characters are the key unit of play in any RPG, and our system hack is going to be no different. For a game modeled after RimWorld, though, we’re going to have to strike a balance between emulation and ease of use, especially considering how many characters may be at play.

Cortex Prime allows for a range of different options for modeling characters, collectively called Prime Sets. Different combinations of Prime Sets lend themselves to different genres, and each one has different rules mods that can be attached to it. Only one Prime Set is required, Distinctions, but luckily it works well for certain traits within the RimWorld framework.

After some consideration, the two core Prime Sets we’re going to use outside of Distinctions are basic ones, Attributes and Skills. Attributes may not be directly used in RimWorld, but giving each character a rating in Physical, Mental, and Social can also be used for stress tracks, recreation type preferences, and other underlying RimWorld properties that wouldn’t fit with other Prime Sets. We’re also going to look into Resources and Relationships, Prime Sets that will be important for the game but perhaps limited at character creation.

Prime Sets

In Cortex Prime, characters are defined by a number of ‘Prime Sets’. These traits define what’s important about your character in the context of the game, and allow for a lot of flexibility in defining what the game is going to focus on. There is one required Prime Set, Distinctions, which provides a set of distinguishing elements of each character. Distinctions work like Aspects in Fate, and a character typically has three of them. Now, Distinctions can also step up other traits, gain SFX, and even have dice ratings, but these aren’t necessarily required elements.

Next up, and the first Prime Set we’ll choose, are Skills. Skill ratings are well known in RPGs and also represent the core of how RimWorld characters are defined. We’ll be basing the skill list off of RimWorld with some expansions, but keeping it to the length of the Cortex Prime example skill list if not shorter. The second core Prime Set we’re going to use is going to be Affiliations. Affiliations has a few examples in the book, with the Marvel Heroic ‘team, pair, or solo’ Affiliation spread being best known. What we’re going to do with Affiliations is break out a few different conditionals around how a character likes to work and what kind of work they like to do. This will begin to model a number of RimWorld traits that form character preferences.

We have two other Prime Sets that will play a smaller though still important role in defining characters. Relationships will be used to track, well, relationships between characters as well as generate links to NPCs that show up throughout the course of the game. Resources will be the main mechanic by which we track gear; like in RimWorld it’s not necessary to track all possessions but some key elements like weapons, cybernetics, and base elements will be modeled as resources.

Distinctions

Distinctions in Cortex Prime are meant to be core traits which, well, distinguish a character. In RimWorld we have a couple different mechanics which could make their way into Distinctions. The first and most obvious mechanic would be backstories. Each RimWorld character has two backstories, a child backstory and an adult backstory. These backstories provide starting bonuses (and penalties) to certain skills, and also give specific additional traits as well. For our game, we may want to keep the idea of having both a child and adult background and using those for two of our three distinctions. For the last distinction, we could go even more specific and look to the RimWorld list of traits. RimWorld traits are all over the map and they’re not all positive, so this may not necessarily be something we use as a Distinction, or if we do decide to go this way it may be random, up to the dice. With traits being the way they are, it might be all right for the third distinction to be a trait which is chosen for characters at game creation, but (like all Distinctions, most likely) random for NPCs and potential future colony joiners.

Another interesting thing about RimWorld backgrounds is that they roll up to larger groups, which could form a basis for how different factions in the game work. We could keep this at the Distinction level or use those broader groups as a set of Affiliations depending on how we want the social group and faction rules to work.

Skills

RimWorld has a list of 12 skills; Cortex Prime’s default list clocks in at 19. We want to cover the range of tasks to be done in the colony, but at the same time not expand the list too much or go for detail where none is necessary. Even RimWorld’s list is a bit inconsistent with detail: ‘Crafting’ and ‘Constructing’ are very close to each other with the gameplay differences being non-intuitive to a RimWorld novice. This is also a place to consider the RimWorld mechanic of work types: Work types are generally meant to restrict what work RimWorld characters are willing to do, but especially in the context of a colony sim, having an extra mechanic around work types will produce more interesting details about what a character is interested in and what drives them, not just what they’re good at. Ultimately, while the RimWorld skill list is a good starting point for what we want to cover, the actual procedures of the game are going to reveal what skill list will be most effective.

Affiliations or Attributes

There are a couple of Affiliations which could provide some interesting detail for characters. Although we’re using Affiliations in a bit more complex way than is described in Cortex Prime (arguably to the point of implementing it twice), it’s still the right Prime Set for implementing some RimWorld character nuance. First off would be the aforementioned work types. Instead of skills, the work types would be broad categories with ratings assigned based on what the character likes or doesn’t like to do. Based on the RimWorld categories, we could see work types of physical, mental, social, violent, and nurturing, with a potential sixth type of ‘dumb labor’ or ‘chores’ for tasks that don’t require a skill check. Of course, the details of this are dependent on how the skills and gameplay loop are implemented, but Affiliations would be the base for establishing what preferences characters have.

Second could be the social groups as noted above, but we could also implement a more detailed list of work conditions. Working with people or alone, outside or inside, night or day, these are all traits in RimWorld which could be modeled through Affiliations. It may also be too complex for the intent of the traits; it may very well be easier to keep these traits limited to Distinctions which use SFX to model the favored (or disfavored) working condition. Depending on what we want to do, it may very well be that Attributes are a better match for work type alignment, which was not clear at the beginning of this consideration.

Relationships and Resources

Both the Relationships and Resources Prime Sets could provide important detail to characters, but for the most part they won’t be very important at character creation. Relationships will start mostly flat across all colonists, with potential for defining additional NPCs that may come up through the course of the game. Resources could be an option during character creation, but it’s unclear if they should be; it may make more sense to keep Resource creation to an in-game option, and have a starting party have a few Resources to share just like how a starting game of RimWorld gives a few weapons and armor pieces. Base workstations will also use the Resources rules, but those will definitely be limited to in-game procurement.

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Character definitions here are intended to model how characters work in RimWorld, with skills and traits governing what characters are good at and what they want to do. As RimWorld doesn’t use attributes per se (though there are a couple coded into characters like work speed and learning speed), the mental model here is also one without attributes.

That said, looking at how we considered Affiliations, it is possible that attributes may work better here. Physical, mental, social, violent, and nurturing provide the spread of activity preferences we want, but they also represent broad inclinations that could work better as attributes. Attributes and skills are also more ‘supposed’ to be linked in this way, though ultimately regardless of which Prime Set we’re technically using, the dice pool is going to be built the same way. We also need to consider how attributes would be used and if we’re going to use mods like Stress, which would depend on attributes to be used by the book. It’s also possible that if our Affiliations list is mostly conditionals, we instead model those with SFX tied to Distinctions in order to keep things simpler; that may make sense because most of the Affiliations wouldn’t necessarily have values unless a character got a bonus or penalty in those conditions.

As much as things could have gotten very complex, it looks like Distinctions, Attributes, and Skills, with SFX on the Distinctions, may end up being the way to go. I think the important thing which I began understanding as I outlined this is that the world of actions undertaken by the characters does not necessarily need to be enshrined in character traits, though we will be writing a lot of detail on it as we go forward.

The attributes we’ll be using will be simple: physical, mental, and social. The Distinctions will have two backgrounds and a third item that can be either freeform, a trait, or even a genotype should we want to lean into Biotech (which RimWorld does). More complex or descriptive traits could work well as third Distinctions; how else are we going to incorporate the fan favorite Pyromaniac? The skill list will be modeled after the RimWorld skill list though with changes; once we figure out how expansive the gameplay loop will be we can finalize a skill list of likely around 15 entries.

Deciding on Prime Sets may not sound like a lot of work done, but it’s helpful here to draw a line as to how much we’re following RimWorld and how much we’re doing our own thing. Also looking into how Prime Sets work can help determine how best to model elements from RimWorld; deciding to use SFX instead of Affiliations took some examination of the rules and once again a willingness to not exactly emulate what’s in the original game.

We are still in relatively sketchy territory, but things will be fleshed out more as we decide how the mechanics are going to work. With base, work, exploration, and combat all needing their own examination, this is going to be where the bulk of the design ideas come together. After that, there are some setting questions that need to be answered in more detail. When we have mechanics and setting, finalizing the lists we established here will be more straightforward, and our system hack will start to look more like a game. In the next month or two we’ll delve into the work loop, and figure out how to turn Cortex Prime into something quite unique.

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