Taking what I call "The Ezra Effect", so named for the character in Star Wars: Rebels , this is designed to allow players to spend XP during the session instead of only afterwards.

For those unaware, in the Rebels cartoon, Ezra is training to be a Jedi. In many episodes of season 1, he learns how to use the Force in a new way during the episode. It's not something that happens between episodes when players would normally be spending their XP.

Since watching Rebels , I've wanted to run a similar story where one or more PCs start with less XP than the others, and their deficit is XP-in-waiting: used to discover a trick, ability or power during play. For that, I came up with this rule:

Untapped Potential

Once each session, a player may spend one Story Point to spend XP on a skill rank or talent. The expenditure must be related to what is happening immediately: if the player is involved in a social encounter they cannot spend the XP on the parry talent, but if they are being attacked in melee that talent is fair game!

The idea is that once per session, each PC can improve their odds of doing—or avoiding—something at an important moment. Only skills and talents directly related to the task at hand can be taken. If it'll make things easier on the PC do it. If it won't change what's happening in the moment, it's a no-go.

With those restrictions in place, why is there a requirement to spend a story point?

48 minutes ago, Noldorian said:

With those restrictions in place, why is there a requirement to spend a story point?

Why not? Elements like story points often end up completely forgotten, so more incentive to use them is just good

1 hour ago, Noldorian said:

With those restrictions in place, why is there a requirement to spend a story point?

Because I want the player to stop and think if they really want to spend that Story Point. If you can do it at no cost, it's going to be used whenever the player feels like it. With a cost attached, however, you need to figure out if it should be used now, or wait until later.

If you do the suggested 15-20XP per session (iirc) you could let them spend a story point to get an XP advance and use it in the way you outlined above. Not more than what you will give out anyway at the end of the session so there won't be XP debt to track. This way the characters won't need to save up XP theay already have which is something I could see many players not being particularly fond of.

I like this idea. In my experience, some of my players are not great about spending their xp every session, so they actually do have a little stockpile at any given time.