Video game systems design is the sub-discipline of game design that’s responsible for crafting all of the elements of the game that the player doesn’t directly control.

For example, while a content designer building Super Mario might decide he throws fireballs and kicks turtle shells, a systems designer would decide how fireballs and turtle shells interact with the rest of the world.

Systems touch every part of the game, and systems designers work on the back end ensuring these systems lead to consistent, excellent experiences.

Systems design spans the spectrum from gameplay systems, to progression systems, to things like camera controls and replays. Every studio needs systems designers, but how central systems design is depends on the game and studio philosophy.

A rogue-like game with lots of procedurally designed content would use purely systems-driven game design as a core cultural pillar.

A narrative-focused game like The Wolf Among Us, on the other hand, might only use a systems designer for the interactive combat cutscenes and interface elements.

Let’s start by looking at how a game designer thinks about a single game system, then zoom out and look at how many interlocking game systems work together to guide the game development process.

What is a Game System?

A game system is any interlocking piece of the game that connects a mechanic with other mechanics or systems. Think of them as the gears behind the scenes that make the game work.

The most common example of a game system is leveling. You gain experience until you reach a threshold, then your level increases. The level system then increases your health, mana pool and damage, which leads to the outcome of taking more hits, dealing more damage and casting more spells.

A more transparent example of a system is a talent tree. Upon level up, you receive a talent point to spend in a talent tree. The tree is a system of requirements and dependencies to restrict the order of your choices.

The World of Warcraft Dragonflight talent trees let players choose between two versions of some effects, for instance a passive benefit or a more difficult but powerful manual option. I used a similar approach making the Mists of Pandaria Warlock talent trees, so it’s nice to see this philosophy still around.

Systems designers structure these trees to ensure players pick up required abilities before ones that enhance them, and to allow players to customize their characters in a meaningful way.

The talent tree is a particularly visible game system located between the level system and the combat systems, unlocking skills and increasing the efficiency of chosen effects, but there are also systems that are mostly designer-facing.

For example, spawning tables tell the game which monsters to place. A systems designer chooses the specific options and frequencies, and connects them as needed to other systems (like making sure a quest npc only appears if you are on that quest).

These are just a few examples of game systems. Game systems designers plan many different systems that come together to create the engine that drives the player experience.

How to Design a Video Game System?

System design treats game systems much like individual parts in a car. Complex game reactions are built of many small pieces working together, even if it seems as simple as turning a wheel or flipping a switch. Bit by bit, the systems combine to form the game’s framework.

When designing a new game system, it is essential to understand the goals of the system so you can avoid excessive bloat or in-game complexity. Once you have the goals, decide which neighboring systems it will interact with and why.

The “why” is incredibly important. Imagine a game that allows you to sacrifice a level to receive an item once a day. Consider everything this seemingly simple idea connects to:

• The level system now needs to support losing levels (impossible in many games)
• Item selection, generation, and storage now needs to work with this ability
• You need a schedule or timer system to prevent exploitation

If you’re making a gritty game about sacrifice and difficult choices, this could be worth the effort. If it’s just a cool idea and you’ll never use these functions again, it’s probably not.

Understanding these interconnections, the goals of each system and your game’s overall focus leads to good systems design.

Now that example is one of multiple systems linking together. What about introducing a new mechanic from scratch?

Individual Mechanics

If game systems are combinations of moving parts inside of the game, then game mechanics are the tools with which the player interacts with the game, and the game interacts with the player.

Think of a bolt on the side of a black box. The game mechanic is the wrench which can grip onto the bolt, turn it and make something happen.

The end result could be turning on a “door unlocked” light, or the top of the box could open and an automated machine gun could pop out. In game systems, the possibilities are endless—so it’s important to know what you’re doing! 🙂

So although mechanics design is focused on specific player experiences, good systems design allows those mechanics to interact with multiple systems in satisfying, understandable, and creative ways.

Even if you’re used to talking about game mechanics as a player, game designers think and talk about them in different ways. If you’re working on your own game (or preparing to start),

Structure and Patterns

A system designer knows just how important consistency and reliability is to a game. If your system design is too chaotic, you’ll confuse or frustrate players.

Even a game of chance needs to give your players a sense that their desired outcome is possible, or they will disengage.

While a creative or design director might be tempted to make every new addition from scratch, great game systems designers know when to reuse the tried and true.

Gradually adding variations to consistent, familiar patterns allows you to increase the game’s possibility space without overwhelming players with new ideas.

This is where the concept of design patterns and structure becomes so essential to game systems design, helping you match each system’s goals to the desired player experience.

Let’s take a look at four concepts in an action role-playing game that feel dramatically different to the player, then describe the underlying pattern they all share:

• The player swings her sword by spending stamina, which regenerates after a few seconds.
• The player casts spells by consuming mana, which replenishes when she sleeps.
• Killing enemies gains her experience, which builds up until it reaches a maximum value and gets exchanged for a level.
• Looting chests or defeated enemies gives her gold.

None of these feel similar to the player, but behind the scenes, these are all examples of resources. Resources all have the same set of data behind the scenes:

• Current Value
• Maximum Value
• Passive Regeneration Rate
• Builders (also known as Taps, like the faucet)
• Spenders (also known as Sinks, like the sink drain)

This model of thinking of resources allows crafty designers and engineers to build game mechanics and game systems which can work the same way across multiple resources.

Let’s look at a quick table of each resource and how they work:

While each concept is its own system, at the core, they all use the resource pattern.

By understanding this pattern, new ways can emerge to change up gameplay. What if you added a banking system where you passively generate gold over time? Suddenly you have the inspiration for a Fable-like system. Or what if experience could be spent like gold in stores? Now you’re recreating Dark Souls soul currency.

Plenty of other patterns like this also exist, such as:

• the tool pattern that changes how the player’s inputs interact with the world
• the projectile pattern that allows you to deal damage somewhere else based on a travel path
• the companion pattern that allows Skyrim to have dogs, humans and vampires alike follow you around the game world

Take a close look at your favorite game and see how many features are really variations of the same patterns like this.

If you find anything surprising or difficult to put into a category, come share your thoughts on our Discord.

The Overall Game Experience

In the couple decades I’ve worked in game design, I’ve noticed that new game professionals, particularly those from programming backgrounds, tend to build systems for the joy of creating new systems.

But at the end of the day, systems serve the game experience. If they don’t, why are they there?

Knowing what systems to create is a radically different skill set that can only be born of experience where you can develop a methodology and framework based on tried and true design principles you have tested first hand.

To make these decisions, modern game systems designers need to be able to keep hold of two perspectives:

• The big-picture view to see how all of the game systems connect together
• The fine-tuned focus to adjust and tune specific values to create the best experience

If you’re working on a game, try analyzing each of your systems from both of these perspectives. Does your system improve the core experience of the game, or detract from it?

For example, look at your game’s physics system. If the big-picture concept is a high-end F1 Racing simulation, then you’ll want to fine-tune every bit of torque, friction and inertia.

But if you’re developing a side scrolling platformer, then you may just want to stop your character in mid-air and quadruple gravity when the input is released.

Neither system is better or worse than the other in a vacuum. It all depends on the game it’s a part of.

Here is a detailed example by Jamie Griesemer, gameplay design lead for Halo 3, on how changing one number dramatically changed the game forever:

Examples of Game Systems Design Approaches

There are as many different ways to approach a game system as there are ways to approach a game. Games are often a reflection of the way their creator thinks about games, rather than an intentional approach, so we should discuss the different strategies of approaching game systems.

Self-Contained Systems (That Make Up Gameplay Loops)

The simplest form of systems design is a self-contained system. This is a system where the outcome or mechanics are exclusive to the system itself. It simply determines a result and lets the rest of the game know what that was.

Some great examples here are lock picking and hacking games from Skyrim or Bioshock.

Self-contained systems don’t have to be as simple as one of these mini-games, though. A random battle from a traditional JRPG can be complex, with many internal systems nested inside it. But it’s still self-contained because the battle itself returns just one result: win or lose.

These types of games chain different systems together as a gameplay loop to create variety.

Exploration Game → Combat Game → Shopping Game → (back to) Exploration Game

There’s nothing wrong with this type of game design. Candy Crush and Merge Mansion are incredibly successful properties, and this sequential staging of experiences makes for a great introduction to systems design work.

When one System is the Game

Next up are games that are a single core system. There is one framework that forms a consistent system for how pieces interact, and working within that system is the entire game.

Strategy card games are the most transparent here. All possible options come from the deck of cards, and all interactions are determined by the basic framework of card costs, card effects, and turn structure.

The card and how it is played is the singular system that drives all other interactions.

Stacklands and World of Goo are other examples of this concept. Stacking up similar items and observing how they interact (or connecting little bars and dots of magic goo) are the core way the game works. You don’t need anything else to overcome the game’s various puzzles.

The entire focus of these games’ development is the exploration of a single premise, often making an unfamiliar or abstract concept approachable.

Modern games in this space focus heavily on internal systemic integrity, ensuring that the rules are consistent and learnable. (Remember, consistency is key!)

Holistic Game Design / Interlocking Systems

Finally, we have game design where you build numerous systems that interlock and interact with each other. The intention here is to create a consistent, but varied game experience.

Games like these are often built upon a strong core game loop. Over the course of development, many different kinds of side loops are created, and systems designers design and code solutions to problems that arise.

An example here is Stardew Valley. While the core of the game is a straightforward farming sim loop (break ground, water, seed, wait, harvest), there are multiple supporting systems that carry the game along:

• Shops exchange resources and introduce a progression of tools and features.
• Interacting with townsfolk and rebuilding the town recreational center creates different sets of objectives.
• The daily time system puts pressure on you to choose your activities well.
• Various other systems operate on progressively larger time cycles, such as animal husbandry, crafting, and distilling resources.

Pretty much all modern games are examples of holistic game design with interlocking systems. The hope is to create different layers of game loops that keep the day-to-day cycle from becoming too repetitive.

For more in-depth analysis and insights, feel free to check out Celia Wagar’s post about design pillars and how to use it in holistic game design.

Systems design as game design philosophy

While all modern games are built of interlocking systems, some designers put this kind of system design at the very center of their game experience.

This philosophy is on a sort of spectrum, with Narrative-driven on one end and Systems-driven on the other.

For example, The Last of Us or The Mageseeker are driven heavily by their story. All systems are in service to the game’s narrative and push hard to keep the story moving along. These tend to not have as much replay value or variation across play sessions.

On the opposite end, Minecraft, The Binding of Isaac, Path of Exile, ARK and Escape from Tarkov use procedurally generated worlds instead of one planned experience. The players’ stories are their own, about creating, destroying or surviving inside the machine of the game’s systems.

Somewhere firmly in between are games like Breath of the Wild, Dredge and Hades. These games have substantial systems and a lot of the player narrative takes the player within these systems.

Remember that ONE TIME you got every Zeus skill on the same run and turned into an absolute raging ball of static?

That’s a systems-driven experience—but you’re also being guided through story-based goals and challenges at the same time.

What games is the systems design approach best for?

If you’re sitting here dreaming of your own pet project, then you might be wondering which approach is best for your game. Well, like all things in game design, it depends.

Most game designers make this decision based on how much freedom they want to give the players to approach problems. Fantastic systems-based design unlocks a lot of freedom for the players within the game—and that’s true whether the game is a systems-based game or not.

Often, this decision is a reflection of the designer. Technical and analytical designers lean into quality systems that reflect their way of thinking and feeling about video games. More artistic designers lean into bespoke experiences that narrowly fit their vision.

At the root, it comes down to how much possibility space you want to support—meaning all of the variations and permutations that could potentially happen in your game.

If you want a game with high replayability, you need a lot of content and a highly systemic approach that makes the experience dramatically different each time. Systems-based games fit this bill.

The risk of a systems design philosophy

Such a decision shouldn’t be made lightly though. Systems-based games tend to lack the same level of refined polish and richness in the final product.

I felt this myself on a recent project I worked on for five years. The team had previously only done bespoke, 6-8 hour games and was now striving for game systems that could withstand 400 hours of play.

The studio was wholly unequipped to handle it. Processes that worked well for our earlier games—like every single asset passing through the game director’s hands—were now far too slow.

400 hours of content became 100 hours of content became 30 hours of content as we hit the limits of our programming, art and animation resources.

Games like Binding of Isaac get around this with simplified art that allows for a minimalist asset approach to expanding the content.

Breath of the Wild struck somewhere in between, with Nintendo-quality polish and a vast world—at the price of a staggering budget and decade-long development time.

Dwarf Fortress’s extreme focus on systems complexity also meant other parts of the game were lower priority, although the graphics have improved since this screenshot.

Even if you do pull it off, a systems-heavy game can scare away players. Dwarf Fortress, while staggeringly detailed and emergent, is unapproachably complex for many players.

The challenge of keeping the big-picture view in mind also becomes harder the more systems you make. If any one of them fails to click with the others, you could fall into an endless cycle of fixes and adjustments.

…and the benefits

That said, if you can pull it off, you can create games with depth, emergent and unexpected gameplay, as well as consistently re-playability.

Final thoughts on game systems design…

Systems design exists at every level, from a single designer tweaking a single value in a spreadsheet, to understanding how challenge and reward vary over an entire game experience, to big-picture philosophies that can shape the entire game.

These tasks are not easy, and require a big-picture perspective of the entire game at all times. While brute forcing system design is a possibility, AAA-level game systems are not created by accident.

Everything from interesting unpredictability to smooth cross-mechanic interaction is only born of sharp, consistent iterative design.

Whatever type of game you’re making, practicing that design approach and keeping these systems design lessons in mind is one of the best ways to improve as a game designer.