Are there any realistic, flexible, and genre-agnostic RPG systems that use actual skill use1 to level up the particular skills of a character instead of the D&D inspired XP based system?

1I call this "Activity Progression." Activity based progression is when your PC doesn't level up on because she reached a particular amount of XP. Instead, each skill has a unique number attached to it which indicates the proficiency level in that skill. To increase the number, you have to practice that particular skill more and more. As an example, if you generally cut through orcs using a long sword, you will become more skilled (or level up) with your sword while your archery skills won't be effected. To increase your spell points, you have to use magic to become fluent in it.


closed as too broad by SevenSidedDie, Oblivious Sage, doppelgreener, Wibbs, Tynam Dec 21 '13 at 12:35

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • 5
    \$\begingroup\$ Do not answer in comments. \$\endgroup\$ – Brian Ballsun-Stanton Dec 20 '13 at 13:57
  • 4
    \$\begingroup\$ "Realistic" and "mathematically complex" aren't really firm descriptors. Please tell us what you think "realistic" means, and maybe provide examples of what is and is not "mathematically complex" (as that means nothing except in comparison to other things). \$\endgroup\$ – BESW Dec 20 '13 at 14:05
  • 2
    \$\begingroup\$ I've regretfully voted to put this on hold as "too broad", since there are so many systems out there that could be a valid answer. \$\endgroup\$ – SevenSidedDie Dec 20 '13 at 21:26

Roll For Shoes is a micro-game that does this

The basic mechanic of the game is that you start off with the skill Do Anything 1 and if you want to do anything you have to roll a d6 to see if you succeed. If you roll a 6 you advance a rank in whatever you were trying to do. So if you were trying to break down a door and rolled a 6 you might get Door Breaker 2.

As you continue to do things in the game, anytime you roll all 6s on a skill role you gain a more specific, higher ranked skill.

While this game is mathematically simple, it is incredibly flexible and definitely genre agnostic. Realism is up to the narrator and characters.

  • 6
    \$\begingroup\$ I think one of the strengths of the RFS skill system is that abject failure provides advancement currency, which means that trying, rather than only succeeding, can be rewarded with advancement. \$\endgroup\$ – BESW Dec 20 '13 at 14:25
  • 1
    \$\begingroup\$ Also, using a simple data tree structure (like nested arrays), it can be create large number of choices as the game progresses giving a completely different meaning to the Job System and other traits like alignment and behaviour. And it's base is simple enough to get started. \$\endgroup\$ – strNOcat Dec 20 '13 at 14:37
  • \$\begingroup\$ @namandixit yes, characters tend to find roles as the game progresses because they have advanced specific skills and skill sets and others have advanced others (some of the advancement is random, but failures allow advancement to be at least somewhat non-random). I've only played this in a single session form, but it has interesting possibilities for longer form games \$\endgroup\$ – wax eagle Dec 20 '13 at 14:39
  • 1
    \$\begingroup\$ @waxeagle: One way to allow some continuity between RFS games, while avoiding excessive skill accumulation, might be to let characters retain one skill of each level between games. (In the variant I've used, I've also let new players start with one character-appropriate skill at 2. Together, these rules ought to keep old and new characters fairly well balanced, since higher skills are, or at least should be, also correspondingly more specialized.) Of course, this would still be more like a bunch of separate adventures, just with recurring characters, than a single continuous campaign. \$\endgroup\$ – Ilmari Karonen Dec 20 '13 at 18:36

Call of Cthulhu does this.

(I'm using 6th Ed. p53 for reference.)

When you successfully use a skill, you can mark it on your sheet (only one mark per skill). Then when the keeper (GM) calls for experience checks, you make a d% roll for each skill you've got a mark next to.

For each skill, if you roll higher than your current score in that skill (skills go from 001 to 100), you increase the score by 1d10. Then clear all the skill marks on the sheet.

This means the only way you can advance in a skill is if you've successfully used it since the last time the keeper called for experience checks.

It's a capricious system which creates a vicious curve: as you increase in skill, you're less and less likely to roll higher than your rank in it on an experience check, so higher skills advance much more slowly than lower ones. Even when you do succeed on the roll, you can get anywhere from 1 to 10 more ranks. However, any skill that isn't used regularly will remain unadvanced for sure, and that sounds like what you're aiming for.


Basic Roleplaying

Chaosium's venerable BRP has percentile skills that advance in this fashion. When skills are used during play, they are marked. At the appropriate time (session end, if memory serves), the player rolls against the existing skill, hoping to fail. If they fail, they roll again to see how much the skill has increased. Rolling to fail means that it becomes harder and harder to advance as your skill increases - modeling many skills in reality. BRP has been used for many genres for many years.

  • 1
    \$\begingroup\$ I think this is a case where each system should have its own answer post. \$\endgroup\$ – BESW Dec 20 '13 at 14:03
  • \$\begingroup\$ @BESW - done! I thought this was frowned upon though... \$\endgroup\$ – gomad Dec 20 '13 at 16:01
  • \$\begingroup\$ In this particular kind of question, multiple answers in the same post are a "shotgun" approach. Users should be able to vote on individual systems, and the OP should be able to accept just the one that was useful. Otherwise it encourages "+1 because I like system X even though systems Y, Z, and Aleph in the same post don't fit the question" problems. \$\endgroup\$ – BESW Dec 20 '13 at 16:04
  • 1
    \$\begingroup\$ Here's the relephant meta thread on the topic, and an older, dissenting thread. \$\endgroup\$ – BESW Dec 20 '13 at 16:10

Burning Wheel

Luke Crane's modern classic also advances skills based on their use. You can see some more details here - but the basic idea is that you need a certain distribution of tests of varying degrees of difficulty against a skill in order to advance it. Again, the system is designed to make early increase easier than later. Burning Wheel is itself a fantasy system, but it has been adapted into games that cover several other genres, so I think it satisfies the genre-agnostic requirement.

  • 1
    \$\begingroup\$ What I especially like is that you have to have a balance of hard and easy tasks to fully learn something, and that, things like advantages/disadvantages bump whether the task counts as easy or not. After a point, you either have to hunt for difficult, and rare tasks, or put yourself under disadvantageous situations to create one. \$\endgroup\$ – user9935 Dec 20 '13 at 16:28
  • \$\begingroup\$ THe thing I dislike about it is that you have to have a balance of hard and easy tasks to fully learn something. Depending on the skill and situation you can find yourself with all the hard tasks marked off and you're not doign anything easy and further hard tests aren't allowed to count towards advancement (by the printed rules). \$\endgroup\$ – Chris Dec 20 '13 at 19:11

Unknown Ponies: Failure is Awesome

While the game was designed to be played as a game set in the My Little Pony: Friendship is Magic setting, there's little tying the setting and system together. The system is also based off of Unknown Armies, which has a very different setting from Unknown Ponies.

In Unknown Ponies, anything can theoretically be a skill1. Unlike its parent game, where you spend experience points to increase skills, in Unknown Ponies your skill increases by 1 when you fail a skill roll. (Hence, "failure is awesome.")

Because of this, the more you use a skill, the more unlikely it becomes for you to increase it further each time you use it2. The game is a percentile roll-under system, so your stat is literally a percentage chance to succeed, with occasional situational modifiers (and increased for your "obsession skill" where you can always swap the roll's digits3, and whenever you utilize your Rage/Fear/Noble passions where conditionally once per session per passion you can swap the roll's digits or reroll).

One advantage here is that you don't have to keep track of twice as many numbers on your character sheet; there's no "experience bar" per-skill, you simply increase the skill when you fail. On the other hand, skill increases are dependent on variance, so some characters may have wildly higher skills than others. On the other other hand, if you have a "power gap" among your characters, the characters with lower skills are the ones that have actually been succeeding at their tasks. (Consider what would happen if skill increases were dependent on success: the players that succeed would be more likely to succeed in the future, and the power gap would expand.)

This system also works well with the "yes, but..." style of storytelling. When a player attempts an action, they succeed4 -- the roll merely determines how well they succeed, or what consequences may result from that action. In a percentile roll-under system where characters start with stats in the 25-35 range, they're going to fail rolls, frequently. When failed rolls don't mean failed actions, players tend to not become as frustrated with the system.

Attributes vs. Skills

This pattern does not apply to a character's attributes in Unknown Ponies. Attribute progression rules are more closely tied to the setting, and is basically spending experience points, like the parent game.

When a character in-game (or a player out-of-game) does something that exemplifies one of the five primary Elements of Harmony (Generosity, Honesty, Laughter, Kindness, Loyalty), that character (or the character owned by that player) receives a point on the associated Friendship Track. These points may be spent to manipulate the actions of NPCs, or alternatively you may spend five points in any combination to receive a point of the sixth Element, Magic (from the lore, the Element of Magic will appear when the other five are gathered). Magic points may be spent to manipulate the result of a die roll (turn critical failure into failure, failure into success, or success into critical success), activate skills the GM rules to be particularly powerful (for those familiar with the setting: think Dash's Sonic Rainboom, or Pinkie's... Pinkieness), or to increase attributes.

Of course, if you use the system and don't want the sunshine-and-rainbows part of it, you could simply fall back to using experience points5. Depending on the tone of the game you're running, you could also potentially disallow attribute increases entirely, leaving characters at their starting values. (Skills may not exceed their associated attribute.) Using Unknown Ponies character creation rules, starting attributes will be in the 30-60 range, or 30-80 for adult characters.


  1. In my current campaign, one of my players (who has a habit of Nice Job Beaking It, Hero [warning: TVTropes]) joked about picking up "Apocalypse" as a skill. If he continues on the way he has, I may end up handing it to him. In one of the Unknown Armies published one-shots, one character has a skill "Making Gobs of Money," another has "Thuggery" and "Shooting Things," and a third has "Faking a Seizure." Standard character creation in Unknown Ponies gives 9 specific skills at 25, and either 2 racial skills at 25 or 50 skill points, depending on race selection.
  2. I won't say "more difficult," as it all ultimately comes down to luck, and you may have some player that keeps rolling 00.
  3. Unknown Ponies is designed to have players play as "blank flanks," children who have not yet discovered their Special Talent, and as such do not assign their Obsession Skill until they reach 40 in a skill. However, the game has rules for starting play as an adult, and Unknown Armies starts all characters with their Obsession Skill assigned.
  4. In a sense, the combat system reflects this, too. Any "piercing" weapon, such as a dagger, will always deal at least 1 damage, even on a miss. Note that "yes, but..." is not explicitly a part of either Unknown Ponies or Unknown Armies; it's merely a style of GMing that can extend across games and genres.
  5. In my campaign, I've generally been handing out 3-6 points of the primary 5 Elements per session per character on average, and 5 of those points may be turned into a Magic point, which can increase an attribute by 1. You can extrapolate from that how many experience points to dole out (and experience costs) if you want to fall back to that.
  • \$\begingroup\$ Wouldn't this system encourage players to spend a lot of time practicing their skills in situations where they didn't have anything to lose by failing? That might be realistic, but it doesn't seem like it would lead to good gameplay. \$\endgroup\$ – Ben Crowell Dec 20 '13 at 23:54
  • \$\begingroup\$ @BenCrowell, It could potentially, yes. In particular, my group ran into a problem where I adapted UA's car chase rules for a footrace, and one of the players failed ten times in a single scene. I contacted the author (Erin Palette) with a suggestion to limit the gain to 1/skill/scene, and she seemed receptive to it; I don't know if or when she'll produce a new version of the rules, but that theoretical future version will most likely include the limit I set in my game, or something similar. (The parent game, UA, has a rate limit for spending XP, after all.) \$\endgroup\$ – Brian S Dec 21 '13 at 1:37
  • \$\begingroup\$ Worth noting, the system has three tiers of difficulty for a roll: the Minor difficulty is an automatic success for any character with 15+ in the skill. A Significant roll is checked against the character's attribute rather than skill value, making it more difficult to fail. It's also, of course, the GM's job to call for a roll, not the player's. \$\endgroup\$ – Brian S Dec 21 '13 at 1:39

As a novel example, the original Battletech board game by FASA used to implement this in a statistical/probabilistic way. Everytime you rolled a double six on skill check, you would be able to advance your relevant skill. Which meant your skills advanced once around every 36 uses.


Universe did this -- you assigned a skill point to that skill whenever you rolled and got a 0. (and/or a 1 or 2, depending on the skill). After certain number of skill points, your skill level increased. The "0" meant that sometimes you received a point when you succeeded, sometimes when you failed.


In practice, what this meant was my players would do silly things to force rolls to increase their skill. "I shoot the tree." While realistic, it didn't lead to a fun game.


Not the answer you're looking for? Browse other questions tagged or ask your own question.