So far I have looked entirely at character ability, and not at external sources of ability.
A common external source of ability is an item of power. In a fantasy setting this is most often a magic item of some sort.
In D&D, magic items often come in several forms. The primary forms are:
- ‘Bottled spell’, an item that gives use of magic expressed as one or more spells. Potions, scrolls, and the base function of magic staves fit this form.
- ‘Bonus item’, an item that gives a bonus to some score or another. Magic armor, magic weapons, and many wondrous items fit this form.
- ‘Special ability’, for lack of a better term, an item that gives the user a capability not previously present. Many wondrous items, rods, magic rings, and some armor and weapon features fit this form.
A single item can exhibit one or more of the above. It is not uncommon that a magic weapon provides a bonus to attacks and damage, and a special ability (many of which add to damage or modify the attack bonus, so I’m not sure they count).
Bottled spells are not interesting. Reliable bottled spells are unquestionably useful, but they do nothing to excite me. I expect I’ll model them some way and won’t spend more time on them today.
Bonus items are even less exciting to me. Sure, yeah, they can make it more likely a character achieves a goal, but functionally “makes another number a little bigger” is about as exciting as carrying a potion of cure light wounds in my pocket. One thing to be cautious of, in a system using 3d6 for task resolution, bonuses have about twice the effect they do in a d20 task resolution system.
Special ability items that let a character do new things — whether by granting new abilities or break rules entirely — stand a better chance of being interesting.
Green Ronin provides a couple of titles that can help me here.
The masterworks system from the Black Company campaign book appears to align well with the bonus ranges I’m looking for. I’m not sure the special abilities granted are a god match, I might need to find another source.
Fantasy AGE special items have similarly-scaled bonuses. I’ll have to review the special ability and bottled spell options.
The relic system in Pathfinder 2e looks like it has quite a bit of potential. Whether an item scales with level automatically or I use the framework to create special items aligning with the levels (same tiers as Echelon uses, levels 1..4, 5..8, 9..12, 13..16, 17..20, even!), I think this could be a good fit.
… lots of details still to settle obviously.
It appears I’ve looked at magic items before, and came to many of the same conclusions.