How Many AP Should Be in an FP? Analysis

[GreatWyrmGold]

Pyramid 3-44 starts off with a section called "The Last Gasp," which includes "Action Points" to represent short-term fatigue. At the end of the section, it gives a suggestion that abilities which cost FP could be converted to AP instead. It mentions a conversion rate of 10 AP to one FP, but as an example rather than a rule, and also suggests changing the rate for "balance".
I decided to explore the effects of different conversion rates.

To do so, I will e xplore the following characters with semi-arbitrary statistics:
* Alexander Dark, an up-and-coming apprentice wizard. HT 11, FP 14, AP 11; Recover Energy 15. (I am assuming that Recover Energy lets you recover FP at double/quintuple rate under The Last Gasp rules; it's never actually explained.) Favored spells include Detect Magic (2 FP), Ice Dagger (3 FP/second charged), and Zombie (8 FP).
* Bianca Alamilla, a revolutionary psion. HT 10, FP 11, AP 14; psionic Energy Reserve 9. (I am assuming that energy reserves return at the same rate as normal FP.) Many of her abilities do not cost FP, but she can burn FP to improve her chance at teleporting (1 FP per +1), and her telepathic Mindstrike attack costs 1 FP per use.
* Chisomo, a cinematic martial artist. HT 15, FP 20, AP 20; qi ER 10. Possesses cinematic skills and techniques including Power Blow (1 FP) and a custom Triple Strike technique (3 FP).
* The Dallas Demon, a supervillain with super-strength and pyrokinesis. HT 13, FP 13, AP 20. Super-Effort ST (1 FP) allows bursts of strength; while most of his pyrokinetic powers don't cost FP, the mighty Hellfire Bomb attack (which immolates everything within a few hundred feet) costs 10 FP.

First, let us determine their FP and AP regeneration under Last Gasp rules.

Spoiler:  

At Mild Fatigue, Alexander Dark recovers one FP per 52 minutes, Bianca Alamilla one FP or ER every hour-and-45-minutes (plus one ER every two hours fifteen minutes), Chisomo every hour (plus one ER every two hours), and the Dallas Demon every hour and a half.
At Severe Fatigue, Alex recovers one FP per 3 hours 45 minutes, Bianca every 7 hours 30 minutes, Chis every 4 hours, and the Demon every 6 hours 15 minutes.
At Deep Fatigue, Alex recovers one FP per 10:12, Bianca per 21:45, Chis per 12:00, and the Demon per 18:30.

Figuring out the average AP recovery rate is a little trickier, but with a quick Python program, it becomes tedious rather than implausible. Going over the how isn’t something I feel comfortable doing, since it’s kinda closely tied to rules that aren’t mine to post on the Internet.
Alexander Dark recovers an average of 4.6 AP per second when doing nothing and 1.5 while evaluating or waiting.
Bianca Alamilla recovers an average of 3.7 AP per second when doing nothing and 0.96 otherwise.
Chisomo recovers an average of 8.5 AP when doing nothing and 4.6 otherwise. (High HT is useful under Last Gasp.)
The Dallas Demon recovers 6.5 or 2.8 AP per second.

And for those who’ve forgotten, under vanilla rules, everyone recovers 1 FP per 10 minutes (except Alexander, because of Recover Energy).

We should now be able to do some evaluations of how various systems impact the characters.
Alexander Dark:

Spoiler:  

Under vanilla fatigue rules, Alexander must rest 10 minutes to recover from Detect Magic. Alex can fire one maximum-power Ice Dagger per 45 minutes, or one minimum-power per 15. He must wait 40 minutes between animating zombies (or ten between the first two).
If 10 AP equal one FP, AP provide only a minor reduction to the FP cost of the spells. He must rest for nearly an hour to recover from Detect Magic, while his castings of maximum-power Ice Dagger would be separated by a bit over 13 hours if he tried to maintain a “sustainable” barrage; with similar requirements, he would need to wait nearly two hours between minimum-power castings. After animating one zombie, he must wait nearly an hour and 45 minutes to animate a second, and 32 hours 18 minutes before a third! (Or he can just wait six hours between each, avoiding Severe Fatigue.)c
At a 5:1 ratio, minor spells can be powered fully by Action Points. Detect Magic can be cast after only a few seconds of rest, while minimum-power Ice Daggers can be cast every few seconds by burning a Fatigue Point each. Maximum-power Ice Daggers still require about six hours of rest to recover from. Alex can easily raise a zombie every five hours or so.
At a 3:1 ratio, Alexander Dark can cast a minimum-power Ice Dagger on nothing but AP, roughly every three seconds. Maximum-power Ice Daggers require more than five hours to recover from. A zombie can be raised every four hours twenty minutes.
At a 1:1 ratio, there are few spells which require actual FP to be cast. Alex can easily sling a minimum-power Ice Dagger every other second (barring intervention by the Random Number God), and even maximum-power Ice Daggers can be cast every five seconds or so (counting both recovery and charge time). Zombie takes a minute to cast, but mere seconds to recover from!

Bianca Alamilla:

Spoiler:  

Under vanilla rules, completely recovering from a teleport rarely takes more than an hour. She can easily throw Mindstrikes around for a typical combat. Half of these can come from FP and half from her ER, effectively allowing her to recover at double speed, letting her recover from most combats within an hour.
If 10 AP equal one FP, getting a +1 to teleport is only a problem in combat, but higher bonuses take longer tolls; +5 means a three-and-a-half-hour recovery period. Mindstrikes can be casually thrown about every 3-4 seconds, assuming she does nothing else.
At a 5:1 ratio, Bianca can trivially add +2 to teleport rolls. Mindstrikes can be casually thrown around every 2-3 seconds.
At a 3:1 ratio, adding +4 to all noncombat teleport rolls, and recovery from a +6 takes less than two hours. Mindstrikes can be used every other second.
At a 1:1 ratio, Bianca can casually add +10 to any noncombat teleportation roll, and sizeable bonuses to combat teleports (depending on how many AP she can spare). Bianca can easily throw Mindstrikes for 45 seconds out of every minute if she spends the other 15 doing nothing.

Chisomo:

Spoiler:  

Under vanilla rules, Chisomo can easily use Power Blow and similar cinematic skills several times per hour. Triple Strikes take half an hour to recover from (barring Chis spending mixed FP and ER), and several can be used in climatic battles.
If 10 AP equal one FP, Power Blow and the like can be used with impunity out of combat (and not just because of Chis’s large AP pool). Triple Strike costs only a single actual FP, if her entire AP pool is available; throwing a few around in one combat requires a couple hours of rest to return to 100%.
If 5 AP equal one FP, Chisomo’s large AP pool and low FP costs mean none of her abilities require dipping into the FP and ER pools. (Oops.) Thanks to Chisomo’s incredible HT, it only takes a couple of seconds to recover from a Triple Strike.
Lower ratios are more or less identical, just letting Chisomo fight longer without resting.

The Dallas Demon:

Spoiler:  

Under vanilla rules, it takes 10 minutes to recover from a little Super-Effort and an hour and 40 minutes to recover from the Hellfire Bomb.
If the ratio of AP to FP is 10:1, the Dallas Demon can easily use Super-Effort, but even expending every single Action Point only reduces the FP cost of the Hellfire Bomb to 8, requiring well over twenty hours of rest to recover from.
If the ratio is 5:1, the Hellfire Bomb takes nine hours to recover from. It takes six hours at 3:1 and roughly two seconds at 1:1.

Now, for some thoughts.
A 1:1 AP:FP ratio leads to some pretty silly results, trivializing almost any FP cost. This may be appropriate to a four-color campaign or the like, but probably not right for most campaigns.
Generally speaking, non-combat abilities have their costs trivialized at higher AP:FP ratios than combat abilities. This shouldn’t be surprising, since AP are primarily a combat-oriented mechanic. Ideally, there would be a simple way to distinguish between combat and non-combat abilities; alas, there is not. The simplest divider would be usage time—anything which took more than, say, a minute (or 15 seconds or whatever) to activate would be a “noncombat ability”. There are, of course, a number of problems. The biggest would be abilities like Warp with a variable activation time, but the wide array of clearly noncombat abilities with short activation times also mess with this metric. Oh, and then there are abilities which can be used both in combat and out of it (Warp comes to mind again).
5:1 and 3:1 seem to be good ratios for combat abilities, and neither has particularly absurd results with noncombat abilities. 5:1 has a couple of advantages; normal humans recover 5 AP per FP spent (though PCs will likely have larger AP pools), and it makes the cost of an Extra AP limitation an easy -1%/level. Of course, 3:1 will work better for some campaigns.


Thoughts? Other points of view or methodologies? Anything I overlooked?

[DouglasCole]

Very nice analysis - thanks for doing it. Seems like that 5:1 point particular shines for making combat resource management matter.

[dripton]

Great stuff. I've only used Last Gasp in a mundane combat game, never in a game with FP-powered spells or psi, so I've never really thought through this in detail before.

Looks like there's unfortunately not a clear answer. It's just another knob for the GM to set at the start of a campaign.

[DouglasCole]

Originally Posted by dripton

Great stuff. I've only used Last Gasp in a mundane combat game, never in a game with FP-powered spells or psi, so I've never really thought through this in detail before.

Looks like there's unfortunately not a clear answer. It's just another knob for the GM to set at the start of a campaign.

My recommendation is to start high at the 5:1 level (costs more per FP equivalent), and then if you find your powered folks gimped too much, tone it down to 4:1, and then 3:1. Lower than that and I think you've got people slinging ridiculous amounts of power around with no real need to pause and recharge. Given the analysis above, I think the 5:1 ratio is a good place to start.

[Tyneras]

I was also leaning towards the 5:1 and 3:1 ratios when I tried to convert Magic to AP. Bit off a bit more than I could chew, there.

I'd recommend making anything that resorts FP restore AP instead, and dump Recover Energy completely.

This would make things like Paut from DF1 restore 12 or 20 AP, and have Lend/Share Energy only Lend/Share AP.

These days I'm of the school of thought that I would make Magical Energy Reserve into Magical AP and give it it's own set of flavorful recovery events.

[Orochi-art]

I'm still a bit slow from new year's eve. You suggest 5:1 or 3:1 ratio. Does this means if the spell was 1 FP; using new system changes that cost into 5 AP/ 3AP?

[DouglasCole]

Originally Posted by Orochi-art

I'm still a bit slow from new year's eve. You suggest 5:1 or 3:1 ratio. Does this means if the spell was 1 FP; using new system changes that cost into 5 AP/ 3AP?

Yes, mostly. There will still be some GM judgement here, in that some things you might just want to say "yes, this used to cost FP when it meant it took 10min to recover. It still costs FP now that each one takes much longer. Suck it up."

But for the trade of FP to AP for powering spells that can be built up (say, dumping a bunch of FP into a fireball spell), you will want to do it at 5:1 to start. So each 1d damage for a damaging spell where 1 FP gave you 1d would now cost 5AP instead.

Extra AP cost 2 per level for "generically useful" AP. Extra FP costs 5 per level. Extra AP that are aspected for magery only might be 1/level with some level of maximum that would be GM discretion. Maybe HT/2 or 5 per level of Magery or something - so someone with Magery 6 and HT 10 might be able to dump 30pts into extra AP for spellcasting only.

I'm just winging it here, as I've never used AP for this purpose.