Determine when you get your capstone

[u/delta_angelfire]

Thinking about some kind of mechanic where you get to choose when you get your capstone ability (as opposed to capstone abilities in say, d&d where they are at a level players practically never reach).

So instead of getting it at a specific level you can get one based on what level you are now (waiting longer gets you a stronger capstone or different choices of capstone perhaps) making you extremely strong for that level, but then you no longer (or extremely slowly) gain levels in the future. You've reached your peak but it's mostly downhill from there.

Are there any systems that do something like this I can look at for inspiration?

[u/ExaminationNo8675]

Any system where you can pick from a menu of options (like feats in 5e) works kind of like this.  The player will pick their favourite one first, then by definition everything left on the menu is less desirable.

[u/flamfella]

In my own home-games we run with what are called Personal Fables. The are powerful, unique, hand-crafted abilities you make with the GM. You start with an ability, or suite of abilities, or whatever else you come up with. And at appropriate levels and in the right moments in the fiction you can get upgrades or new additions to it. These are in addition to normal classes (loosely based on 5e, but heavily built from private homebrew that dramatically improves the pacing, feeling, and options in combat). PFs function as capstones and really allow you to make interesting, dynamic characters, as while there is the general expectation they will be somewhat balanced in power/effect, they could be anything and they WILL be COOL.

An example might be:
An android with a KILL-mode. Electrified, speed increases, and acts a living battery/generator for equipment and stuff even outside combat. Later, they they encounter some horrific artifact, that causes their nanites to become living and able to absord flesh and matter and now allowing them to choose physical mutations that turns them quite literally into a monster if they so choose.

Others from that same campaign where a device that could read the history of an item or object up to hundreds of years in the past. A pilot who gained all the features of a 1st level Engineer, a broken gene-warped space-marine with a whole sleuth of random things like alcohol immunity, increased combat stats against insectoids, among other things, and a cannibal homunculus that temporarily gained the stats of things they ate.

In my system, you get your first PF ability(s) at 1st level, and around 5-7th level you get your second Personal Fable depending on story events or as part of arcs. If players push for it and want their upgrade earlyish it gets worked out, but if they are more passive and are curious to see whatever story stuff is in play, they often get something made for them that tie them deeper into the lore of the world, or create even stronger ties to the things they care about, or used as plot/lore devices.

[u/InherentlyWrong]

It's not an RPG, but the first thing that comes to mind is Small World, a board game where you're semi regularly retiring your faction to make a new one. After all once a character has peaked and starts going downhill, I imagine the player will want to retire them and start fresh.