Hacking XP part two: applications


In part one of this post I discussed experience and its uses in gaming. In particular, I brought up the ideas of:

  • Tailored triggers, in which different characters gain XP in different ways, allowing everyone different goals in play.
  • Pre-meditated experience, in which you choose which mechanical thing to advance (in whole or in part) before you set out to gain experience.
  • Combining these, the idea of advancement tailoring triggers, in which your triggers are determined by your choice of advance.

The theory discussion got a little long, so I finished up after about a thousand words. Now I’m going to hammer out a possible application of experience using the above techniques.


The first question is: why? There’s a strong argument that every piece of complexity you add to a game should be justified by how it drives play. This should be the case regardless of which school you come from: rules for rules’ sake will at best hold up play and at worst destroy the mood and tone of the game.

A good way to benchmark rules (in my opinion) is to compare them against the simplest working analogue: that is, the least complex rule that you could slot in place to do the job. There’s a couple of candidates that immediately spring to mind for the simplest working analogue when it comes to experience:

  • Episodic XP: At the end of every session (or story-arc, etc.) the GM awards each member of the group a number of XP to spend as they like.
  • Basic XP: The GM or system assigns a set list of tasks. By achieving these tasks, characters may gain XP, which they can then spend when they see fit.

The Episodic XP system is a great example of a system that gets out of the way. It does just enough that your characters can progress as the campaign unfolds. The Basic XP system is the sort of thing you’d see in a “traditional” game in the vein of D&D. It’s slightly more structured than the Episodic XP system, and it rewards individual achievements over the group’s.

Both of these are low-complexity XP systems. Every time this custom home-brew XP system becomes more complex than these, there should be some sort of overriding benefit: otherwise why bother adopting some sort of more complex XP system in the first place?


Assuming I’m designing this thing well, my rules should guide play towards some theme or structure. Here are the general themes I want to have in this XP system:

  • PCs develop short- or mid-term goals based on how they wish to improve themselves
  • These goals lead to player-driven scenes and vignettes in play

This means that you, the player, get to decide how your character will try to advance, and you are then rewarded for showing your character’s advance on screen.

Now we have some goals, let’s get to work.

Structure of XP


XP and advancement are tailored and compartmentalised using a concept called keys. Taken from The Shadow of Yesterday, keys are discrete characteristics with attached triggers. For example, if your character is a dashing swordsman they may have:

Key of the Daredevil. Gain 1 XP whenever you show off in combat or a dangerous situation. Gain 2 XP whenever you put yourself in the line of fire to demonstrate your courage or skill. Gain 5 XP whenever you impress a notable ally or enemy with your skill and panache.

This key describes something about your character and provides three triggers. It’s a perfect example of tailored XP gain. It’s considerably more complex than either the Episodic or Basic XP models described above, but it immediately rewards you for play specific to the personality and nature of your character. It also allows you to give flags to the GM: that is, things or subjects you want to see addressed in the game. For example, when you choose the Key of the Daredevil, you’re telling the GM you want fights in precarious settings where it’s possible to perform flashy stunts, and so on.

The Shadow of Yesterday starts characters with one key (and the chance to grab another one immediately) while its immediate ancestors (Lady Blackbird and Marvel Heroic Roleplaying spring to mind) prefer two. Six triggers for each character appear a good number to drive play, and the GM can always add “whole-group” keys for a given plot1. I believe two keys is a good number, but (and here’s where stuff starts getting experimental) I want to add two more keys. I’m going to call these vocational keys, and they’re going to be telling you how your character improves.

Vocational keys

Here’s how vocational keys work: at character creation you pick two advances you want to strive for. If you’re playing FATE, here are some advances you could go for:

  • Advancing a skill at the cost of another skill
  • Replacing an aspect with another aspect
  • Replacing a stunt with another stunt

These all qualify (in FATE terms) as “minor advances”. When you start out, you pick two advances, specifying which skill, aspect or stunt you want to advance. Each advance you’re striving toward gives you a vocational key. I imagine that for a fully fleshed-out system you’d have a number of key templates sitting around ready to be adapted, or even a key or two for each skill. For example, if I want to increase my piloting skill. I could then take a vocational key that looks something like this:

Vocational key: piloting: Gain 1XP when you enter a scene carrying something related to your piloting training. Gain 2XP when you take the helm in a dangerous or tense situation. Gain 5XP when your piloting gets you out of overwhelming trouble.

Another difference between vocational keys and regular old keys (let’s call them “character keys”, since they talk about your character’s personality or nature) is that vocational keys have an XP goal on them. This goal could be between 10 and 25 XP, with the exact amount depending on the magnitude of goal you wish to achieve2. Every time you gain XP from a vocational key, you mark off that many XP towards your goal. When you gain XP from a character key, you mark off either of your vocational goals, your choice3. Once you hit your goal, you apply the advance - and pick a new goal to work towards.

A sample set of keys: two vocational, two character

Cost and payoff

The cost (in terms of complexity) of this system is pretty apparent: you now have four keys to keep track of, which means a grand total of twelve different triggers. Also, when you gain XP you need to fill in a little set of boxes. XP is no longer a simple “fill up the bar and grab the advance” matter.

The payoff is hopefully player motivation: if you want to become a better pilot you need to seek out situations where you get to pilot. While simple study may be enough at low levels, once the goal amount hits 20 XP or higher you’ll need to seek out more challenging situations.

Another payoff is colour: this system lets you know what your character will be doing in their off-time, or in down scenes, or in the background of scenes that are about other characters. If two other characters call on you, you can always be lounging in your bunk reading the memoirs of a famous pilot (ding, XP gain).

The question here: is the payoff worth the cost? This is something that playtesting will have to reveal. Success is when the XP system guides play but doesn’t dominate it, encouraging particular scenes to happen, but letting them still feel natural.

Carrot-driven play

There’s one last point I’d like to address in this post, and that’s what failure might look like. There’s currently a drive in story-gaming towards mechanics which reinforce particular methods of play. This is no exception: if you play your character according to their personality (character keys) and goals (vocational keys), you will be mechanically rewarded.

There’s arguments for and against this. The usual argument for this runs something like this:

We want these things in our game. If we give people rewards for including these things in the game, we’ll get more of it. We’re encouraging the sort of play we want to see.

The argument against sounds like this:

If you want these things in your game so much, include them. Their presence in the game should be its own reward. If you start handing out rewards for doing these things, you’re no longer including these things in your game because you want them there, you’re including them because you want to improve your character.

Both arguments hold merit. I feel that the game should hold a middle ground between the two: you should be encouraged to frame scenes or follow motivations that enforce the game, and these mechanics should subtly guide the game towards particular issues or themes, but you shouldn’t feel forced that way. Veer one way, and the game becomes somewhat unstructured, a variant of “pass the stick” storytelling in which the plot can be directionless and conflict dull. Veer the other way and the game becomes a series of check-boxes, almost a board-game where your character is now a set of stats you want to improve. This second scenario is a very real possibility once you start deploying rules to guide themes.

Should this system suffer from such carrot-driven play, that’s a good sign that I’ve got too many triggers on the table. One simple way to reduce this is to drop the number of triggers per key. Lady Blackbird does well with one trigger per key. Alternatively, it could be a sign that four keys per character is just too many on the table at one time.

The ultimate test of this system is, of course, to try it out in practice. I hope to do this in the next few months. And that will demonstrate whether these XP rules provide a framework for character motivation and colour, or simply make the session a game of hit-the-keys.

  1. In this case, you gain XP when you hit particular scenes or accomplish particular events in a given storyline. It’s effectively a giant carrot to motivate the party towards particular points in the story. 

  2. Advancing a skill to average at the cost of another skill may cost 10 XP, while gaining a new stunt without losing an old one would probably be pushing 25 XP or even higher. 

  3. I should note here that the low-XP goals are often time-limited in TSoY and similar games: once per session for 1XP or 2XP goals isn’t uncommon. This means you’re not overplaying aspects of your character at risk of turning them into a caricature of a person.