Shadowrun System Analysis: Part One

Shadowrun has a long history in the information security community. I cannot count the number of people with fond memories of Shadowrun and who love to share stories of their previous adventures. The game has a special place for me. I have spent a lot of time learning about tabletop roleplaying games and how they are designed, and I would like to share some of my insights.

In this series of posts I am going to analyze the systems of Shadowrun Fifth Edition. I have a lot of opinions about Shadowrun's design, and in particular the design of Fifth Edition Shadowrun. I am planning on talking about the following elements:

  • Core system
  • Reward System
  • Gamemastering
  • Other Systems

This post will be focused on Shadowrun's core system mechanics and then briefly touch on how I do system analysis. Core mechanics are the mechanisms that resolve conflict, resolve action, and determine the general flow of the game. Following posts will delve deeper into the system interactions in Shadowrun.


Every roleplaying game has a core resolution mechanic. A core resolution mechanic is the means by which actions in the narrative are resolved.

In Dungeons & Dragons the core resolution mechanic is 1d20+[Modifier] vs Target Number. The Modifier is determined by a combination of skill bonuses and character statistics, and the Target Number might be someone else's 1d20+[Modifier] or the Difficulty Class assigned to the task. In Dungeons & Dragons, non-player characters (NPCs) use the same resolution mechanic as player characters (PCs). If you meet or exceed the Target Number then you succeed at your action, and if your result is lower then you fail. Dungeons & Dragons is a binary success-fail system.

In Apocalypse World the core resolution mechanic follows 2d6+[Modifier]. On a 10+ you succeed. On a 7-9, you succeed partially or must make a hard choice. On a 6 or lower, you miss.. If you ask a probability expert you will learn that most results of two six-sided die will fall between 7-9. In Apocalypse World most of your actions in the narrative will partially succeed and complications will arise.

Shadowrun's core resolution mechanic is a dice pool system. In Shadowrun Fifth Edition your dice pool for an action is based on a relevant skill and attribute, then you roll that many six-sided dice and for every five and six that show up on those dice you count a hit. This is called a test. The three types of tests in Shadowrun are Success tests, Opposed tests, and Extended tests. Some key values are skill, attribute, limit, threshold, and for extended tests the test interval.

A Success test is represented by Skill + Attribute [Limit](Threshold). An opposed test is similar in that the success threshold for the test is replaced by a test made by your target. An extended test is represented as Skill + Attribute [Limit](Threshold, Interval).

Skill represents your character's training in a specific task. A character's attribute represents your character's strength, agility, reaction, willpower, and so on. Most tests have a limit which represents a limitation that prevents a player from rolling too many hits on a test. You can only have hits on a test up to your limit. The threshold is the number of hits that are required to succeed on a test. Extended tests have an interval, which represents how long each test takes and you carry over your hits between tests until you meet the threshold.

Everything in Shadowrun is handled by this system from shooting to not getting shot, and anything in between. The Shadowrun core rulebook spends fifty pages explaining the lore of the world before presenting this information. This vital information is then overshadowed by character creation which spans another fifty pages.


For every group of four dice you roll, on average, at least one of those dice should result in a five or six. Unless the gamemaster says otherwise, you can 'buy' one hit for every four dice in your test's dice pool instead of rolling the test. Shadowrun never connects buying hits on tests with the narrative importance of skill rating 4. Each skill rating from 1 to 12 are described in narrative context.

A skill rating of 4 is considered 'Professional.' Therefore, a professional locksmith, with a skill rating of 4, who is suited for the task, an agility rating of 4, will always succeed at any Average (Threshold 2) locksmithing tasks. Tools add to the user's dice pool and limit for a specific test, and so Professional tools would be rating 4. Given professional tools, a professional locksmith can be reasonably assured that with a bit of effort they can complete Hard (Threshold 4) tasks often enough to make an honest enough living.

I have called this out because this is indicative of both how thoughtfully designed the mechanics of the game are and how poorly they are presented. This interaction contextualizes Shadowrun's balance choices, and enables players to make more meaningful choices during character creation.

Edit (Clarity): Buying hits is worse on average than rolling dice on a test. The purpose of this mechanic is to bypass low-stakes tests that you are likely to succeed at.


The core resolution mechanic in Shadowrun is flexible. It effectively resolves any situation that one can encounter in play. This creates a smooth game flow when the players or the gamemaster know what pools are required and how the results affect the narrative. The core resolution mechanics take up six pages in the core rulebook.

Every conflict is resolved in exactly the same way, regardless of the situation. The combat rules include an action economy comprised of complex actions, simple actions, and free actions. You can always take a free action on your turn, and you may take one complex action or two simple actions on your turn.

All combat involves similar steps.

  1. Attacker rolls against Defender. Example, in meat-space: Pistols+Agility [Accuracy] vs Reaction+Intuition
  2. If the attacker wins, then add their net hits to their attack's Damage Value. Example, attacker 2 net hits: Ares Predator DV 8P + 2 (net hits) = DV 10
  3. Defender resists the damage. Example, meat-space: Defender rolls Body+Armor. Defender rolled 4 hits. DV10-4 = DV6. Defender takes 6 damage.

This same process occurs whether you are hitting someone with a taser, throwing data spikes in cyberspace, or hurling conjured acid. The only difference is what skills and attributes are used at each step.

At the start of a combat turn, players roll initiative and when a character takes a turn they reduce its initiative by ten, and any character who has an initiative above 0 may make another turn on the next initiative pass. This continues until everyone has an initiative of 0 or lower and then everyone rolls fresh initiatives. This initiative system is difficult to describe but plays smoothly. It ends up as a simple core system that plays the same in meat space, the matrix, or in astral space.

The core combat mechanics are simple enough that I summarized everything you need to know in a few paragraphs. The combat section of the Shadowrun core rulebook spends fifty pages explaining every possible modifier one may encounter. Experienced players who have memorized all the exceptions and situational modifiers like cover, wind, visibility, and distance can flow from one action to the next as fast they can roll the dice. The problem is that combat, like many sections of the game, has a simple core system and pages upon pages of modifiers. For any possible situation in combat that might make it easier or harder to shoot there is a modifier to consider.


Shadowrun comes from an old school of game design: simulationism. I am certain that it is alive and well and that it has a group of loyal followers. Every gun has unique stats or features, and every runner has a personal favorite. There are dozens of tools and at least one of them is exactly what you need to open that door. The more careful runners will spend hours planning every detail of a run to command as many positive modifiers as possible and to minimize negative ones.

Fortunately we have learned a lot about design since the days of Dungeons & Dragons Third Edition (Revised) and Shadowrun First Edition. There is a new trend in game design that demands more than a series of generic resolution mechanics. Games can deliver specific experiences and guide players to specific types of narratives through clever use of mechanics.


Smarter people than I have created a set of questions that guide and focus the design of games.

  1. What is your game about?
  2. How is your game about that?
  3. How does your game reward players for engaging the things your game is about?

These questions work very well for designing games. I have found a lot of use in them for analyzing systems outside of games. If we look at those questions we are examining a couple things in particular.

  1. What is this system intended to do?
  2. How does this system work to deliver that?
  3. How does the system incentivize users to engage in the system as intended?

With this set of questions we can examine practically anything and come to an understanding of how the mechanisms involved function and what the results of different interactions will be. It is not important to answer these questions in order when you examine an existing sytem. All that matters is that you work your way through each mechanic you can interact with until they all have context and you have sufficient answers to each question.


There is a good core system in Shadowrun Fifth Edition. There are problems with the tacked-on systems that I am going to explore in future posts. I will examine different mechanisms and interactions through the lens of these three elements: intentions, mechanisms, and incentives. My goal is to show how to analyze systems using Shadowrun as an example.

The first system that I am going to explore in my next post will be the reward system in Shadowrun.

Support the Author

Devon Taylor (They/Them) is a Canadian network architect, security consultant, and blogger. They have experience developing secure network and active directory implementations in low-budget and low-personnel environments. Their blog offers a unique and detailed perspective on security and game design, and they tweet about technology, security, games, and social issues. You can support their work via Patreon (USD), or directly via ko-fi.