The High Concept
In times of crisis, heroes can accumulate great functional skill and power extremely quickly. There’s little time to think, only time to act, limitations falling again and again without the indulgence of hesitation. The gods look on from the great beyond, subtly lending their weight to their champions and granting them access to magics beyond what should be possible, and insights into the universe that would normally take years to understand.
Yet when the crisis ends, there comes a crash. Just like a surge of adrenaline in a fight, you can blow past your limits for a time, but you cannot keep it up indefinitely. Inevitably, the crisis is averted, the constant fear and stress abates, and the gods turn their wills upon another area of the cosmos. The heroes take a much-needed rest, and find much of their monumental power quickly slipping away. Not long after their victory, they remain more powerful than they were when they started, but not nearly as powerful as they were when they faced their primary antagonist.
In short, they can go on more adventure paths without being massively overleveled.
The Motivation
I’m not the biggest fan of the speed of leveling in D&D, particularly since 3e. If I recall correctly, 3e assumed about 13 average encounters per level, of which you could handle around four per day: around two months of constant action to hit 20th level from 1st. 5e is even faster: if you consistently hit the expected XP per adventuring day on page 82 of the DMG, it takes 23 days to get to 20th. Combined with the consistent deprioritization of downtime, this means that most campaigns can race to high level very quickly in world time.
Obviously in real time this is probably multiple years of play, and the numbers were chosen for maximum fun. But it’s still weird. Most of the settings of D&D have the assumption that high-level NPCs took most of their lives to get there, but all the players ever see is their teenage PCs consistently becoming movers and shakers while still teenagers. So something that brings setting assumptions in line with played experience has been a quest of mine for a while.
This is also not just a D&D problem. In Brandes’ Mage: the Awakening game, we had some problems with XP expenditures. Particularly, the game didn’t stop us from just dumping nearly all of our XP into upping gnosis and primary arts, so we were very quickly able to go toe-to-toe with what were meant to be the biggest threats of the setting. The strongest mages in the setting books had a much more robust array of character traits, with high values in multiple abilities and powers, but PCs can go a long way when all they have is a giant hammer looking to figure out how to make every problem a nail.
One of the solutions Brandes and I brainstormed after the campaign ended was the seed of this post’s idea: mage PCs could only buy gnosis and arts with per-session XP, but periodically most of this XP would be ejected from these powers and spent on other character traits, resetting the powers to a more reasonable level.
Ultimately, this mechanism lets you give the PCs a rush to great power, but also a longer term play that lets them go through multiple adventure paths and gradually grow into characters with a lasting integration with the setting.
The Justification
Normally, if you want to both keep your PCs and play published adventure paths with minimal tinkering, you have a big problem. Paizo and WotC mostly make adventure paths that start at 1st level and go to the mid-teens. If you finish one of them and want to do another, you’re going to have to either re-stat everything to higher level or just assume that they’re going to blow through most of the first several books with no challenge. At best, if you prepare early you can slow down level progression and alternate between similarly-leveled modules in multiple adventure paths (straining your creativity to explain why the plot jumps around so much).
However, the trick of D&D‘s XP progression is that it’s geometric: you can start out significantly more powerful than the path intends, but it doesn’t take long before you’re only slightly higher level than expected. If you start at 6th level instead of 1st, by the time the modules expect you to be 10th level… you’ll be 10th level. Admittedly, you’ll hit 11th significantly sooner than intended, but you’re still within one level of what is expected. 5e doesn’t have the truly expansive differences in level at the high end that earlier editions did, but even if you started at 10th, you wouldn’t hit 20th level until the modules expected you to be nearly 18th level.
This means that you can leave the PCs with some sense of progression: they aren’t as high level as they were at the end of the last AP, but they’re still higher level than they were when they started it, and they get to keep their best magic items.
The Mechanics
Figure out what level the PCs are likely to end the first AP at, and at which level you’re comfortable with them starting the second path. Divide the first path’s max XP by the second path’s starting XP. That’s your ongoing divisor to generate each PC’s “true” level.
For example, in my game they ended the first AP at 17th level, and I wanted them to start the next at 6th. 17th is 225,000 and 6th is 14,000. That means that there’s an approximate divisor of 16. With 225k XP at the end, the PCs’ “true” level was based on 225k/16 (a little over 14k) XP, and, thus, 6th level.
During subsequent APs, level the PCs up normally from whatever level they got reset to (e.g., if they started it at 6th, act like they started with 14k XP and it’s 9k XP to 7th). Then at the end of the AP, remember what effective XP total they started the current AP at and subtract that out when you recalculate their true total at the end of the path. In the 17th to 6th example, if they ended the second path at 239k effective XP, you know that that was another 225k after removing the initial 14k, so they have 450k total (e.g., now at true level of 7th based on that 450k/16 = ~28k).
Could you also just have the PCs start a level higher each subsequent AP and not have to do all the math? Yes. But a lot of players are happier if they know there’s some kind of objective calculation going on in the background (even if you deliberately fiddled with the calculation to get the results you wanted, which was basically an extra level per AP).
The PCs get to keep at least three of their favorite pieces of gear they had at the end of the last AP. Assume the rest got sold for investment capital or given to a museum. In 5e, this is very easy to manage because many PCs are only going to care about their three pieces of attuned gear anyway. Give them an arbitrary amount of starting cash: the rest got spent on living through the downtime, and possibly spent on investments (in most APs, it really doesn’t make a difference if the PCs are building up impenetrably fortified home bases, since they’re traveling around wherever the adventure needs them).
Each time through, consider giving the PCs an option to rebuild their character slightly stronger. I’m giving my players an extra point-buy point and/or bonus feat/stat improvement, and also letting them rearrange class ability choices and multiclassing based on their updated conception of the character (rather than just resetting them directly back to what their sheet was when they were that level the first time). If I was still running in Pathfinder, I’d consider gradually opening up expanded class options, lowering entry requirements for prestige classes, or tacking on mythic levels.
In setting, the PCs’ accomplishments weren’t undone. They still have the fame/notoriety earned, even if they can’t still back it up with high-level spells and abilities. While if an NPC asked, they might not be able to take out a dragon like they could before, since subsequent APs are going to ask them to handle only low-level threats for a while, they’ll probably still feel like pretty big damn heroes for a long time. 6th level characters go through goblins at a hell of a clip.
The Synergy
One fun synergy of this system is that it makes the retired adventurer NPCs make a hell of a lot more sense. Modules are full of post-arrow-to-the-knee characters that supposedly adventured for years and yet are within a couple of levels of wherever the PCs are expected to be at that point. It’s likely because if they were genuinely high level, the players would be like, “if the barkeep is a 14th level Fighter, why doesn’t he just go clear out the mines of kobolds?” But it further strains suspension of disbelief in many cases.
However, under this system, it actually makes perfect sense. These characters never shot up to high level like the PCs did, because they never dealt with a world-threatening crisis: their “true” level and effective level were usually really close. It takes a lot longer to get to hundreds of thousands of XP when you’re only fighting low-level stuff. Those 4th-8th level barkeeps that used to be adventurers could have had many years of dealing with small-time local problems to get to that point, and feel fully justified in their retirements.