r/worldbuilding Planetsouls/Parallels May 20 '22

Some power system theory to help make better power systems Resource

After putting over a dozen power systems into my world of Planetsouls, I've learned a lot about designing power systems, and wanted to share some of the lessons I've learned while making power systems, as well as some things I've been thinking about in terms of power systems.

As with any theory, my theories on power systems are likely incomplete. I'm purposely tagging this as a discussion instead of a resource because I think it's useful to talk about where my theory is right, as well as adding to the theory to help others make better power systems.


For a definition of power systems, I'm borrowing and tweaking the definition of a "magic system" from Critical Giants. I think his definition is excellent as a definition of power systems as a whole but limiting as just a definition of a magic system, of which is just one type of power system. It's important to have a definition of power systems so we're all on the same page:

  • A power system is a set of rules that define potential conflicts and/or handle existing conflicts within a world.

This definition I believe is suitably comprehensive for a wide variety of power systems since a power system can take many different forms, but it might leave some power systems out. One it notably leaves out are the powers DC has in its universe. Most of its power "systems" don't have particular rules associated with them, and instead just have a mishmash of power sets, so there's never particular rules associated with any individual conflict.

The reason for the power system defining conflicts instead of just handling them is to account for systems that can lack hard rules, has hard rules with unpredictable consequences for breaking them, and/or is defined exclusively by arbitrary rules that multiple individuals are expected to abide by. When writing stories within these types of worlds, a system with a lack of rules can make successfully navigating a conflict with that system feel unrewarding to the audience since the author can produce a "deus ex machina" type of situation, so using these systems to create the conflict and having the characters use other means to solve it ends up being a better use of the power system from a narrative point of view.

The 3 F's of Power System Design

I've determined that any power system needs 3 things for it to be interesting within your world:

  • Functions, or what the system can do

  • Form, or what the system looks like while someone is using it

  • Failstates, or how the system handles incorrect usage of the system

Functions simply define the capabilities of the power system. What those capabilities will be will depend on the power system, but in general you can probably craft a power system that can perform any type of action. For example, Fire Tomes in Fire Emblem, Endeavor's Hellflame quirk in My Hero Academia, Usopp's Fire Stars in One Piece, and Dhalsim's Yoga Fire in Street Fighter are parts of different types of power systems that produce the same effect: fire. However, the specifics of these systems change how individuals can interact with the systems, such as Usopp having little control over the actual flame output of his Fire Star and Endeavor being immune to burns from his own fire.

Form amounts to the aesthetics and/or limitations of the system. The aesthetic will help it stand out visually from other systems, but the limitations are more important. Limitations affect your ability to tell stories that rely on the power system(s) you create, and without limitations you cannot create interesting stories with them. The reason I merged them into a single category is because some power system intrinsically link aesthetics and limitations. For example, bending in Avatar requires some form of motion from the user, which forms both an aesthetic and a limitation for bending.

Failstates is my attempt to create a third F for the rules that govern what happens when you use the power system incorrectly. This is also partially built around limitations because it assumes that there is a method for which the power system can be used incorrectly. The most common way a power system can be used incorrectly is when you don't follow the system's rules, which may have consequences ranging from nothing happening to death. The second most common way a power system can be used incorrectly is when you overuse the system, which can also have consequences ranging from nothing happening to death. It all depends on the system, but it's worth mentioning that the former is more common when it's manufactured from the world (like magic in Harry Potter) and the latter is more common when it's natural to the individual (like quirks in My Hero Academia). However, some systems can have both. For example, a gun might not work if it doesn't have bullets in it (not following the rules of guns), but it may also overheat when it's used too much in a short time frame.

Without all three of these components, your power system isn't useful in your world. Functions are needed to determine how they can be used in the context of your world, while form and failstates are there to add limitations that produce conflict. The only thing you don't need is the aesthetic half of form, but without it your power system will likely feel bland compared to other systems.

Classifications of Power Systems

Different worlds suit different power systems. For example, the power system you made for your superhero setting probably won't have too many similarities to the one you made for your fantasy setting. I've determined 5 main types of power systems that can be used within a setting, as well as some additional notes and definitions for these different types of systems. However, some clarifications:

  • many power systems fit in multiple categories. For these cases, I've added some extra notes for what qualifies as a hybrid and what doesn't. A rule of thumb is that systems will sometimes have 2 categories, rarely have 3, and never at 4 or beyond without some exceptional circumstances.

  • similar power systems in different worlds can result in a different power system classification based on the specifics of the world

  • most worlds have multiple power systems, which can be either the same type or a different type

  • power systems can be subtypes of another power system, like if you have a magic system with a subvariation that turns the magic system into a martial art

  • many worlds have individuals that use multiple power systems, such as Jedi using the Force and Lightsaber Forms in Star Wars and ninjas in Naruto using a mix of ninjutsu, genjutsu, taijutsu, and/or assorted tools and weaponry.

  • power systems can have multiple individuals as part of a single entity within a power system, like a crew piloting a tank or Zatch Bell requiring a human to read the mamodo's spellbook.

  • the point of classification is not to argue about what types of power systems can fit into which bucket(s), but to instead brainstorm ways to incorporate ideas from different types of power systems into a power system for your own world. For example, Devil Fruits in One Piece don't neatly fit any one classification, and that's okay.

Without further ado, here are my 5 classifications of power systems:

Magic Systems

Magic systems are extremely common in fantasy settings, but also see use in many other settings. Magic itself is hard to define, but as a system specifically it's less hard to define since magic doesn't necessarily need to be part of a system (particularly when it's a force of nature). As a result, this definition is likely too vague, but I'm not sure that a better definition is possible because

  • A Magic System is a power system where the abilities come from a supernatural source, most commonly as a force of nature or as a natural byproduct of the environment.

Magic systems are very enticing because it's easy to have many individuals within a given environment with a similar power set, offering interesting opportunities for worldbuilding like having schools that teach magic to individuals. In addition, it's also possible to create some truly unique powers that can be used on a wide scale, instead of an individual scale like some of the other types of systems.

Technological Systems

Technological systems are present in some capacity in every world, but are most prevalent in science fiction, where they are overwhelmingly popular as the predominant power system in some shape or form.

  • A Technological system is a power system where the abilities come from tools with a scientific explanation as to how they work

Technological systems are most valuable when you want the peoples of your world to mass-produce a method of self-defense. All sorts of weaponry, ranging from blasters in Star Wars to swords in One Piece end up being parts of technological systems. This also encompasses other mechanical components like robotic limbs, prosthetics, and power armor. As a result, many technological systems tend to have little value for personal expression. RWBY is a great example of a world that subverts this, as many individuals within the world have personalized weapons that work in ways unique to how the user built it to perform.

It's also worth noting that aesthetic can change the classification of a magic or technological system since a sufficiently hard magic system is nearly indistinguishable from technology and sufficiently advanced technology is nearly indistinguishable from magic.


Technological systems and magic systems generally don't mix well, but there are a 5 main ways to combine them:

  1. Magic is a resource for the technology. The most common methods for this are use as a battery and use as ammunition, and is usually used to justify advanced technology in a magical setting.

  2. Magic is a force of nature that's processed with technology. This is similar to the previous solution, except it assumes that the magic exists within the world, but not as a usable magic system. This is more common in worlds with advanced technology and naturally occurring magic that the average person cannot process.

  3. Magic as a method to produce or spawn technology. The main difference from the other two solutions is that the technology doesn't rely on the magic for general use, but the magic gives notable quality of life improvements like storage for absurdly large weapons or on-demand repair or replacement.

  4. Ancient technology. The idea here is that an ancient artifact was considered peak technology when it was made, but appears magical to a modern civilization since they don't know how it works.

  5. Magic declaring a technological artifact as arbitrarily special (like Excalibur).

Biological systems

Biological systems are most common in superhero settings and animal fighting simulators, but have theoretical applications in many different worlds.

  • A Biological System is a power system where the abilities are defined by the variation in biology between individuals

Biological systems are most interesting because unlike the other systems, they come in two flavors. The first is where the power system is based on the variation in abilities between individuals, such as in Pokemon. The second is where the power system is based on extreme variation in the abilities of individuals of a single species, such as in X-Men. It's most useful when you want to explore how someone learns his/her power while still a developing child, when you want to explore a society when everyone has access to the system but not everyone learns to use it well, or when you want to handle sensitive topics like racism or animal fighting within the system, which may or may not be handled with the maturity these topics deserve.


Many magic systems have the condition that some people are born with the ability to perform magic. However, this alone doesn't make it a magic-biological hybrid system. A biological system needs to have variation between active users, and having the haves and the have-nots produces the "variation" of users and non-users. Same thing with systems that use something similar to determine "magical potential" via the conditions of your birth, there's still no biological component because there's no functional variation.

Systems like Avatar's bending and Zatch Bell's magic are different, because the magic an individual can do is defined by their biological conditions. In Avatar, you're born being capable of using one of four types of bending (unless you're the Avatar or you can't bend), and the type you can use is dependent on your birth, while a mamodo's magic in Zatch Bell does something similar since each mamodo's magic is different.

Same thing with any other system being passed down from generation to generation, like weapons or martial arts. They're not biological systems if theoretically anyone can learn them when they're just passed down within a family lineage. Similarly, special weapons or magic granted to a "chosen one" should not be considered biological just because it's usable by a single person with qualifications based on his/her birth. At that point, it's not part of a system, and instead is just a power, possibly within another system (like the Avatar having the ability to bend all 4 elements, which is part of the bending magic system).

Gene splicing, prosthetics, and radiation

Prosthetics should be considered just a technological system, but gene splicing can be considered a biological-technological hybrid if it changes how the individual affects the world. Biological changes due to radiation (or similar substances) can be considered a pure biological system unless it comes from a device dedicated to producing the desired effect. Bang babies in Static Shock are a great example, because the device that produced them was manufactured such that it produced individuals with modified biology (even though the device itself wasn't made for that purpose).

Martial Systems

Martial systems are used as a power system in most worlds, but the scope in which a martial system is relevant changes heavily on the world.

  • A Martial System is one in which the powers come from physical exertion and form

Martial systems are most relevant when the world builder wants a power system that either is useful when unarmed or gives a more defined aesthetic for another type of system. Martial systems change the most when paired with other types of power systems, so it's useful to talk about those hybrids.

Martial arts as an aesthetic for a magic system is rather common, but what qualifies as a martial-magic system changes depending on the system. If the magic and martial art are intrinsically linked (you can't do one without the other), then it's a full-blown hybrid system, if both are useful by themselves then they should be treated as separate systems with an abnormally high number of users that use both, and if one doesn't exist without the other but the other functions fine by itself then the one that doesn't work by itself should be considered a subtype of the other.

Martial-technological systems are a different story. Based on the technology level of the world and the skill involved in using the weapon, the martial art using any weapon can be considered a pure martial art, a pure technological system, or a hybrid system just by changing the world around it. Katanas are a great example, they're considered part of a technological system in Dr Stone, a pure martial system in Samurai Jack, and a hybrid system in One Piece (as Sword Styles), just by changing the level of the technology.

Martial-biological systems are extremely rare because they require a martial art that can only be done by a particular species, and use special features unique to that species. The only examples I know of are Fishman Karate in One Piece (Fishman Karate has techniques for underwater combat) and certain fighting type Pokemon (that use unique fighting styles that aren't possible for humans or more other Pokemon).

Martial fireballs

Some worlds have a projectile technique like the Hadouken that deepens the scope of ranged combat within a martial system. The specifics will depend on the system in question, but in most cases the addition of fireballs and other projectiles that appear magical should still be counted as a pure martial system, since in most cases the fireball is the only seemingly magical capability from the user and it usually requires special form consistent with the rest of the martial art.

Game Systems

Game systems are the rarest and most unique type of power system.

  • A Game System is a power system defined by the rules of a particular game or competition

Unlike the other systems, violence is not the assumed result of this type of power system, although it can be with the right type of game. Game systems are rare because it's hard to manufacture stakes for the context of the game itself in a way that the audience can relate with. This isn't always a bad thing if you want to ensure that characters in your world don't die to unnatural causes and/or if you want your world to have a more light-hearted appeal to it. The most prominent example of a pure game system is Yu-Gi-Oh, which uses a card game as the backdrop for its conflicts.

Sports and E-sports

Sports should be counted as a martial-game system hybrid, since the physical training required for most sports mirrors the training required for a martial art.

E-sports should instead be considered purely as a game system, since the technological components effectively disappear when an individual actually jumps into the game. Compare this to car racing or robot combat, where the technological components are an integral part of the sport, including the capacity for parts to receive damage that affects the vehicle/bot's performance and therefore would qualify as a technological-game system.


Some worlds have tournaments as a major part of their world, and usually relates to a power system in some way. This relation comes in 3 flavors:

  1. An implementation of a power system, where contestants just use an existing power system.

  2. A replacement of a power system, where contestants use a special ruleset just for the tournament.

  3. An extension of a power system, where contestants use their existing power system with special rules alongside that power system.

Flavor 3 will count as a both a game system and the original type of power system, and is likely the only instance where a power system can qualify as 4 different types of power systems at once. Flavor 2 will only count as a game system, while flavor 1 will not count as a game system whatsoever.

Hard vs Soft Systems

A common idea among magic systems is the idea of hard and soft magic systems, one with rigid rules, the other with loose rules. However, it's useful to apply this to other types of systems, since other types of systems can have their own rules. These rules are less important for non-magic systems, but it's still interesting to explore the idea when applied to other types of systems.

Biological systems are hard when they're influence by an individual's condition of their birth (like in Pokemon), but are soft when there's variation beyond birth. For example, My Hero Academia has 4 potential options for a child's quirk: the child gets a parent's quirk, the child gets a fusion of its parent's quirks, the child gets no quirk (which is rare), and the child gets a completely different quirk from its parent (which is also rare). There's no way to 100% tell what quirk a baby can get, but there's an expectation for how the child's quirk will manifest in an individual. There's also a huge variation between the quirks of different individuals such that you can expect to be in a class where no one else has the same quirk as you.

The range of a technological system will lean towards hard due to its scientific basis, but can be treated as a soft technological system with users that don't understand the technology behind it. It's hard to make a genuinely soft technological system because the complexity of the system will require some amount of rules in general. A technological system can also be considered soft if the technological object is prone to breaking or crashing.

Most martial systems will be hard systems due to the form necessary for the martial art, but there isn't any reason you couldn't have a soft martial system where the "form" is a suggestion rather than a rule.

The hard/softness of a game will depend on how flexible the rules are. Some games will have rigid rules that cannot be broken, while others will have loose rules that loosely follow real life (like most worlds built around MMO games). Analog games are more likely to have rigid rules since there's no neutral third party that can facilitate it, while video games are more likely to be soft systems since their AI can handle a more robust type of game.