Girl holding golden dice.

RPG Design Choices #3: Game Mechanics

If you understand your genre, characters, and moods, you should have an idea of what kind of game play will be best for your game. Is it gritty and realistic, requiring lots of intricate rules to simulate physics?  Is it an epic game where superhuman powers matter more than mundane skills? How easy or difficult will it be for characters to die?

An important piece of game play in RPGs is chance and uncertainty.  It’s not the only part of game play—there’s also player collaboration, setting, plot, dialogue, etc.  However, chance is the unique piece that makes roleplaying games, well, games.  Without the element of chance, RPGs become a sort of improv reader’s theatre.  Chance creates the game by requiring players to strategize.  The chance of failure encourages characters to think through which actions will be most effective in a certain context.  Higher and lower chances of success at particular tasks differentiates characters, giving players unique abilities to contribute and the need to cooperate.  Characters chance failures can force players to re-evaluate their strategies and try something new.  Even the failures of non-player characters can force the game master to improvise in ways that create memorable victories for players and make the game more exciting.

The RPG design question at this point is how do manage chance in your game? How will chance make the game challenging and exciting for the players, and will that chance lead to the kind of outcomes you’d expect for your RPGs genre? You’ll want to be very careful how you calibrate chance.  Too much chance of failure, and the game ends early in frustration and/or character death.  Too little chance of failure, and the game is less challenging and less exciting.

The classic way to introduce chance is to roll dice, and there are many variants of how to use dice in an RPG.  Here are a few common approaches to using dice:

  • The ‘roll above’ model, where players attempt to roll above a target number (higher means more difficult).  In a simple case, you may have a six-sided die and players have to roll a 5 or 6 to succeed on a difficult task.  In these cases, character stats typically add to the die roll, increasing your chances of meeting or exceeding your target.  Perhaps a character has a +1 in an ability, they would then only have to roll 4 or higher to succeed.
  • The ‘roll below’ model, where players attempt to roll below a certain target number, usually defined by the character’s stats.  For example, in a system based on a single 6-sided die, a character might have a stat of Strength 3.  For strength-related tasks, the character would have to roll under their strength.  If they increase their stat, they increase their chances of success.  Bonuses would be added to the target to make it easier to roll under, penalties would be subtracted.
  • The dice pool model: the characters roll one or more dice, with a fixed target.  For example, perhaps 5 and 6 are always a success.  However, if a character is more skilled at a task, they get to roll more dice, increase their chances that at least one 5 or 6 will appear.  Difficult tasks may require the character to get more than on successful die roll.

Really, any of the above (and many models not discussed) can be calibrated to challenge players and create characters that are good at some things a less good at others.  Some good resources for using dice to create chance in an RPG: an in depth discussion of dice mechanics and an online dice probability calculator.

Of course, dice aren’t the only way to make roleplaying games chancy or challenging.  Here are some other common ways to introduce chance in a game:

  • Use a counter or token.  Sometimes players have control over when counters are spent, sometimes they don’t (hit points).  Even when players have control over when and how to spend their counters, this serves to limit a character in a slightly different way than a high chance of failure.  At a certain point, the character runs out of counters and either they are limited in their actions or something else bad occurs.
  • Use cards like a board game, although board games don’t typically bias results towards a character’s strengths or weaknesses. If you want to support characters with different skill levels getting different out comes, you may have to get creative.
  • ‘Can I?’ Players simply ask the GM, who serves as arbiter of what’s reasonable.  This doesn’t really introduce chance (certainly not for the GM), but it serves as a mechanism that limits characters so that players aren’t free to choose any course of action and be successful.  Sometimes this is a better way to resolve trivial or easy tasks without slowing the game down with dice rolling; however, over use can lead to bickering, accusations of bias, and also takes the element of chance out of the picture for players controlled by the GM.

There are even more creative methods.  Dice poker.  Games of physical skill.  But here are a few questions that might help you tune your use of chance:

  • Are characters clearly differentiated by what they are good at and not good at?
  • Do players have a way to enhance their chance of success or recover from a drastic failure?
  • Is it possible for player characters to die?  How easily?
  • What degrees of success or failure does your game support? Is it pass/fail? Do you include ‘critical’ failures or successes?  Many levels of success or failure based on die results?
  • How much is success determined by chance, and how much by character stats?
  • What types of outcomes should not be left to chance?
  • Is chance treated different for different types of actions? For example: independent actions (picking a lock), cooperative actions (two characters ramming a door to break it down), and resisted actions (one character ramming a door, another trying to bolster the door from the inside).

While you experimenting with different types of chance, you can judge them by

  1. How does this affect pacing? Does it slow down game play?
  2. Do the random outcomes seem appropriate for the genres and stories that the RPG is focused on?
  3. Is there any aspect of chance that makes gameplay in the RPG unique?

In Legendary RPG, here are just a few of the game mechanics decisions we made:

  • The decision to go with the very straight forward additive dice model
  • We play-tested both with one 20-sided die, and with adding 2 ten-sided dice together.  Players commented that the 20-sided die seemed to result in a lot of critical successes and failures, so we use the two tens—extremely high and low rolls were much less likely.
  • Right now, we’re experiment with not using the familiar ‘counter’ of hit points.  Instead, we count damage on the character, and the character rolls to stay conscious after taken certain amounts of damage.
  • Legends don’t die very easily, so we have rules for incapacitation, but actual death is not up to chance.  It’s a choice the player and the game master can make for a character.

If you’re curious about Legendary’s game mechanics, sign up for our email list to have chances to play test it yourself!

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