To Start With
Start your PCs off with the equivalent abilities of whatever level the referee deems a suitable starting "power level" for the campaign. They may be novice adventurers (1st level), or may be more capable in their chosen professions.
Instead of characters' skills and abilities automatically improving through the course of their adventures, this system assumes instead that long periods of time are required to hone skill -- the typical timespan of an adventure (a few days or weeks perhaps) not being sufficient. Of course time is also money, to at least some degree.
It is thus envisioned that characters will advance in more meaningful ways -- deliberately choosing to hone the skills they feel they need to achieve their goals (whatever those may be), rather than simply getting "free stuff" when advancing in level. In situations where a campaign goal is pressing urgently upon the PCs, personal advancement may simply not be an option -- in this case other possibilities must be explored by characters (acquiring the aid of NPCs who do have the required ability, for example).
Mechanism for Advancement
The basic mechanism is that a certain time period must be spent in training of some kind, and that a roll of Xd6 against a relevant attribute (roll under or equal) determines whether the training was successful. The number of d6s rolled is determined by the level of the ability which the character wishes to advance to (i.e. the step above his or her current ability level), making it more and more difficult to advance as the character's ability improves.
The training roll can be attempted any number of times, although each attempt entails a length of time.
How Many d6s?
- A fighter can improve his or her attack bonus by +1 by rolling Xd6 against STR, where X is the equivalent fighter level for the next step up in attack bonus. (For example, a fighter with a +3 attack bonus, the equivalent of 2nd level, would have to roll 3d6 equal or under their STR in order to advance.)
- A specialist can improve any skill by rolling Xd6 against a related attribute (referee's call), where X is one greater than the current level of the skill. (For example, a specialist with 3 in 6 stealth would have to roll equal or under their DEX on 4d6 in order to advance.) The exact nature of specialists' training is open to negotiation -- this makes some skills easier to train than others (it's easy to imagine how a character could improve at foraging and hunting, but how exactly does one improve at searching?).
- A magic-user or cleric can advance one spell-casting level (a step up on the "spells per day" chart) by rolling Xd6 against INT (for magic-users) or WIS (for clerics), where X is the highest spell level castable by the next step on the chart. (For example, a magic-user able to cast three 1st level spells, two 2nd and two 3rd per day, the equivalent of 6th level, would have to roll equal or under their INT on 4d6 -- as the next step includes 4th level spells -- in order to advance.)
- Depending on how the referee handles known spells for magic-users, they may be required to make a roll against INT on Xd6 to learn a new spell, where X is the level of the spell.
This is very open to each referee's and each campaign's requirements, but a rough idea per training attempt might be:
- Fighter attack bonus: one month.
- Specialist skill: one week.
- Spell-casting level: one month.
- New magic-user spell: one week.
Training time must be spent pretty much devoted solely to that activity. In periods of down-time between adventures, PCs may have other responsibilities, and thus may not typically have the time required for training, without making special arrangements.
Special circumstances may give a bonus to a training roll (i.e. effectively increasing the relevant attribute for the purposes of the roll). The referee may grant a bonus from things like expert tutelage (which will naturally cost money) or consulting tomes or libraries (for spell casters).
Training Through Adventuring
Over the course of a long adventure (weeks or more) during which a character has regularly and intensively practiced a skill, the referee may allow a training roll to be made. A short jaunt into a dungeon would not usually qualify, but a three week long military campaign (in the case of a fighter) may.
The assumption is that "adventures" are, in general, short bursts of intense activity dotted through the normal lives of PCs.
What About Hit Points and Saving Throws?
Good question... I'm not sure about that yet. Any ideas?
One could of course simplify this whole thing into a "roll to advance a level" system, but I quite like it being a bit more fine-grained than that.