Experiential Advancement (Secret Santicorn 2025)
My Secret Santicorn gift is for Errant Thinking, who asked for:
โGame mechanics for experiential or diegetic character advancement. Bonus points for some emphasis on social experiences.โ
I've been thinking a lot about leveling and downtime a lot lately, so I was super happy to get this prompt.
The following mechanics are intended to be bolted on to any rules-light old school system. This is a quick and dirty framework, which means it has not yet been play tested; I hope to do so soon!
What is an experience?
An experience is something that a PC has done, witnessed, or survived. Examples include showing a gorgon her own reflection; surviving deadly venom from a great spider, or falling into a spike pit. Experiences should be measurable and discrete; โclearing a dungeonโ is not an experience, but โswitching the Eye of Zarlon with a sack of sand to fool a pressure trapโ is. An experience is something you boast aboutโor try to drown while carousing.
I'm shying away from โdiegeticโ here, as I have problems with โdiegetic advancementโ on two fronts. One, the term โdiegeticโ doesn't really mean that; and two, I feel the term has been bandied about a little too much in OSR circles to the point where everyone has an idea of what they think it means while also not committing to laying out how it works.
โExperientialโ has a lot less baggage and wound up more closely matching what I ended up writing, but I still have a few qualms about how close to is to โexperience points.โ Weโll figure it out!
How do we advance?
In order to benefit from an experience, a player character must return from the site of the experience to a safe place (such as a town, castle, etc). The safe place must be somewhere where people are around to hear about itโcamp at the mouth of the dungeon wonโt cut it.
The PC must spend downtime equal to 1 week/HD reflecting on their experiences, relating it to others, and gaining new insights. At the end of this time, the PC makes an experience roll to determine what new benefit their experience has given them.
Once a PC has gained such a benefit, they canโt reflect on the same or similar experience again. A PC can only reflect upon one experience per level.
The base experience roll is 1d6.
The roll is modified by the type of safe place where the tale is related: -1 for an outpost, 0 for a village, +1 for a town or larger.
Every 2500gp (knock a 0 off for systems without XP for gold) spent confers a +1 bonus to the experience roll. This represents research, paying minstrels, etc.
Bringing in a relevant NPC mentorโsuch as an older thief in the Eye of Zarlon exampleโthat could help you reflect on the experience confers another +1 bonus.
The referee can assign a bonus or penalty at their discretion, should some factor be at play. Perhaps the PC relates their experience to a minstrel, or commissions art depicting it.
What benefits can you get?
For rolls 3 or less, a simple numerical benefit is gained, usually a bonus to attacks, saves, AC, etc. relevant to the experience.
Results of 6 and higher are where it starts getting cool.
For rolls 10 or higher, the PC receives the 3 or less result, then rolls againโre-rolling any 3 or less result.
For most cases, the benefits should be extraordinary or uncanny, but not overtly supernatural. If the experience was supernatural, like being turned into a newt, go buck wild.
Example Experiential Advancement Tables
Example table: Showed a gorgon her own reflection
3 or less - +2 on Saves vs Petrification.
4 - Your allies gain +2 on Saves vs Petrification as long as you are conscious and able to advise them.
5 - When averting your eyes from a petrifying gaze, you only take half the normal penalty.
6 - You can reroll a failed Save vs. Petrification, but must take the second result.
7 - You can unerringly tell when a statue is just a statue, or someone who has fallen victim to petrification.
8 - You learn an herbal remedy to reverse petrification, e.g. a fragrant branch of yore.
9 - When you fail a Save vs. Petrification, you turn to stone on the next round instead.
10 or higher - You get the 3 or less ability and roll again.
Example table: Switched the Eye of Zarlon with a bag of sand to fool a pressure trap
3 or less - Pressure plate traps you interact with go off on 1-in-6 instead of 2-in-6.
4 - You move your encounter rate speed in one direction when a trap is triggered.
5 - You can determine how much an object weighs by looking at it.
6 - You can swiftly assemble a forgery or substitute that will fool someone who is rushed, distracted, in the dark, or none too bright.
7 - If a trap being triggered would destroy a treasure or object, you can snatch it away at the last second.
8 - You automatically detect pressure plates as part of normal dungeon movement. You don't necessarily know what theyโre connected to.
9 - When a pressure plate trap is triggered, you have one last chance to disarm it as a first-level thief, or as a thief one level higher.
10 or higher - You get the 3 or less ability and roll again.
Example table: Turned into a newt by Gothgar the Stupendous; got better
3 or less - +2 on saves to resist polymorphing, mutation, etc.
4 - Effects that would transform or mutate you offer you a choice of the original outcome and an unknown result at the refereeโs discretion. I like Skerplesโs d1000 Mutations and The Metamorphica Classic Edition.
5 - Temporary changes to your shape last half as long; permanent ones fade after a year and a day.
6 - You retain your mental faculties and speech when polymorphed.
7 - Small objects and equipment, such as rings, amulets, etc transform with you, becoming vibrant markings on your plumage, fur, etc.
8 - A failed save against an effect that would change your shape, mutate, or polymorph you works only partially. Roll 1d6 for: 1 head 2 arms 3 legs 4 body 5 senses 6 special: wings, gills, etc.
9 - Once per full moon, you may return to the shape you were transformed into.
10 or higher - You get the 3 or less ability and roll again.