RyanM
2007-05-25, 11:02 PM
Update!
Okay, I've spoiler tagged the old post for archival purposes. I'm still working on an in-depth writeup of the rules which are finalized, so I'll just go over the highlights. Actual set rules will come eventually.
I've decided to call it the RGP system. Officially, it stands for Realistic Gaming Platform. But you can call it Role Gaming Play if you want. :smallbiggrin:
General:
There are ten statistics.
Strength - pretty self-explanatory.
Perception - general awareness level in addition to sensory acuity.
Constitution - physical toughness, immune system strength, etc.
Stamina - pretty self-explanatory.
Agility - whole body agility and speed. Running obstacle courses, gymnastics, walking on a narrow beam, etc., rely on Agility.
Dexterity - hand-eye coordination and fine motor control. Playing the piano, brain surgery, shooting a gun, etc., rely on Dexterity.
Intelligence - pretty self-explanatory.
Intuition - being able to subconsciously pick up on subtle clues, even if you don't consciously notice them. Something like if your Intuition is high enough, the GM will ask you to make your own whatever check, so that you know something is up. Or maybe for stuff like a Spot check equivalent, you roll vs. Intuition and Per seperately. If you pass the Int check only, you get a general feeling or something, like "being watched," or "bad feeling," or "hidden treasure." If you pass the Per check only, you actually notice the whatever, and where it is, but get no clues as to the real nature of what you see/hear/whatever. If you pass both, you both notice the thingie, and you get some clue as to what it is. And if you pass neither, it was just the wind.
Charisma - physical attractiveness, "emotional intelligence," general people skills, je na sa quois (I can't spell it!), etc.
Willpower - the ability to do unusual, even supernatural, things through sheer force of will.
Hit points are based on physical size. One pound of body weight (for a living earth creature) equals one hit point. A 180 pound human has 180 hit points. (some weapons, like elephant guns, do more damage to larger creatures)
Your character's ideal weight is based on their stats. Racial base weight plus strength, plus constitution. The best way to gain hit points is to put points into strength and con (see advancement, below).
Your weight can also change based on how much you eat (there will be set rules, but the vast majority of players will simply declare that they eat the normal amount to maintain their ideal weight, and be done with it).
Losing a lot of weight due to malnutrition penalizes Strength and Constitution by the amount you lose (but eating sufficient food later will restore most or all of your Str and Con, depending on how severely you starved). Always pack enough food!
If you become fat, you get penalized for Agility and Stamina, to the point where if you exceed about 500-600 pounds (for a human), you're basically unable to walk under your own power (maximum mobile weight depends on stats). You do get the extra hit points, though; weight in pounds = maximum hit points. In a modern day type campaign, where food is plentiful and you can get a car and a gun, minor obesity isn't so much of a disadvantage. The extra hit points may be worth it depending on your skills.
When your hit points reach zero or below, your stats are all halved. You can go down to a negative score equal to your Willpower before there's a risk of passing out. Gotta roll vs. Willpower every turn to stay conscious.
If you go down to a negative equal to your maximum HP, you gotta roll vs. Willpower or die.
For simplicity, you can make it so that normal NPCs just collapse unconscious or dead when they reach 0 HP. Most NPCs will have an atrocious Will score anyway.
Combat skills:
The attack roll is a percentile (D100) roll. You must roll under your % chance to hit to score a hit.
The attack roll is also the damage roll. The number you get (rounded up to the nearest 10%) is the % of base damage you do. Base damage is weapon-dependent (also strength, when appropriate).
Because your % chance to hit caps the damage you can do, unskilled opponents will fall quickly and not hurt you much, even if they have about the same number of hit points and the same weapons and armor as you.
In the included campaign, weapons do pretty realistic amounts of damage. One or two good, 100% base damage hits with most weapons will be enough to incapacitate most people.
Weapon skills are broken into 3 categories with 4 skills in each one, and then a 4th "write-in" skill. For a given weapon, you use one skill from each category, plus your write-in skill if you have it.
For melee, the skills are Size (Tiny, Small, Medium, Large), Balance (Tip, Middle, Hand, Flexible), Type (Edged, Pointed, Spiked, Blunt).
I really suck at naming stuff! Name suggestions for skills and stuff are always welcome!
So for example, the longsword uses Medium Size, Hand Balance, Edged or Pointed types (depending on if you're chopping or stabbing), and "Longsword" write-in skills.
A katana, on the other hand, uses Medium, Middle, Edged, Katana. Thus someone who has exclusively trained with the longsword, if forced to use a katana, would be able to use their Middle and Edged skills, and weild a katana about half as well as a longsword.
Because of the write-in skill, a generalist can never be as skilled as a specialist.
The cap for each skill is 100%, so your max base chance to hit is 400%.
Defense skills'll be similar, still working on 'em.
Still working on refining ranged combat skills, too. So far the tentative system is Release (Dynamic, Static, Fast Trigger, Slow Trigger), Velocity (Low, Medium, High, Instant), Form (Thrown, Bow, Pistol, Longarm).
Unarmed has got me stumped, need ideas.
At percent chances to hit over 100%, you always hit. You roll, then add your chance to hit over 100% to whatever you rolled. So at a 115% chance to hit, if you roll 45, then you do (45 + 15 round up) 60% base damage.
Critical misses and hits occur when you roll a 0 for your second digit on the attack roll (multiples of 10). Whether it's a critical hit or critical miss depends on whether you hit or missed.
Severity of the critical hit or miss depends on how high or low you rolled. A critical miss at 90 would be rather minor, while a critical hit for 90 should be pretty good. A critical hit at 10 is nothing special, but you gotta be really drunk to miss if you roll a 10, so a critical miss at 10 is pretty bad.
For a critical hit, you take the % you rolled, add it to your % chance to hit for that attack, round up, and there's the damage you do. So if you've got a 65% chance to hit and roll 40, you do 110% base damage.
Thus, critical hits always do more damage than a regular attack, even if you just roll 10. None of that double damage and then you roll a 1 crap.
00 (or 100) is always a critical hit, and always does +100% damage. Ouch. Fortunately, PCs are immune to critical hits, except from boss-level encounters.
Critical misses cost you action points on the next turn, and lower number ones may cause you to hit yourself or something (effect table maybe?).
General combat:
It's an action point + movement point system. One turn is 2 seconds. An average human will have about 10 action points and 10 movement points per turn.
One movement point will let you walk 1 foot, run 3 feet, or sprint 5 feet (if you sprint, it takes several movement points to stop when you're done).
Using one type of point also uses up the same number of the other one, unless you use both simultaneously (need to explain better!).
I.e., you have 8 movement points and 10 action points. You have a laser pistol that takes 5 action points to fire. You can shoot the laser pistol twice, without moving. You can use 5 movement points to move, then shoot once. You can shoot once, then use 3 movement points to move. You can use 8 movement points to move, while simultaneously shooting twice, but at a stiff penalty to accuracy due to moving while shooting.
Armor. A given set of armor will have a percent coverage rating (with %s given for each general area of the body, for calculating partial sets and stuff).
Take your coverage %, round down, divide by ten. A hit roll ending in that number or less hits armor (if it hits at all).
Because of the rounding down thing, an armor has to have true 100% coverage to protect against critical hits. Power armor, magically reinforced armor, forcefields, something like that. True 100% coverage is also required to protect against some special types of damage, like blast/concussive damage from explosives.
Attacks that hit armor are reduced by some % (subtract it from your roll and round up), based on type of damage. Slashing (draw cuts, like slicing, as opposed to hacking), hewing (chopping), piercing, blunt, and ballistic. If it reduces the % to zero or less, no damage is done.
Some weapons will do multiple damage types. You always use the most advantageous damage type, for everything, in that case. So it may be one type for one thing, another type for another.
Example. So let's say you attack some dude with 85% coverage armor, and you have a 60% chance to hit. His armor has 50% reduction vs. the damage type your weapon does. You roll a 58. It hits, but hits armor, so you do (58 - 50 round up) 10% base damage. Then you roll a 39. It hits, and you manage to nail an exposed area, so 40% base damage.
So a single roll tells you whether you hit, whether it was a critical, how good/bad of a critical it was, whether the attack is affected by armor (if you hit), and the amount of damage you did (if hit). Only additional roll would be on an effect table if you get a really good critical hit or really bad critical miss.
Non-Combat skills:
Trying to get a 3 category, 4 skills in each, plus a write-in thing here, too.
Currently, best I've come up with is Background (Social, Mechanical, Survival, Abstract), Scale (Mental, Fine, Gross, Environmental), Sense (Awareness, Touch, Kinesthetic, Emotion).
There's probably a lot of room for refinement there, need ideas!
Advancement:
No levels.
Doing difficult stuff (including training/practice) gives you experience points that can be put towards a relevant skill or stat.
Increasing a skill or stat by one requires the goal skill/stat level squared char points. So going from 59 to 60 requires (60^2) 3600 points.
Just training or practice gives you 1 XP per minute. So reaching 100% in some skill (25% each in four skills) requires 1.5 months of intensive training (8 hours per day), or 1 year of casual training (around an hour a day). Reaching 400% in some skill requires 8 years of intensive training. About right for some insane martial arts guru or whatever. Gains through actual real world experience are much faster, obviously.
Need equations for combat experience and junk.
If trying to transfer stuff to/from D20, one D20 XP equals about 20 RGP XP.
For increasing stats, the maximum you can increase any stat to is double your starting stat, or double your starting intelligence, whichever is higher.
IQ should never be your dump stat. Intelligence is easily the most important stat there is. "Work smarter, not harder" is a reality. Having a high strength score is a combination of both physical brawn, and knowing how to use your strength most effectively and efficiently. Even the strongest person can throw out his back if he doesn't know the best way to lift, stuff like that.
Going to have something similar to feats, except they have to be learned from like, a guru on a mountain or whatever, so they're campaign dependent.
Players will also be able to make their own "feats," and even teach them to others, but how good they are depends on IQ. Once again, IQ is probably your most important stat, regardless of your playings tyle.
Misc:
Alignment in the D&D sense won't exist.
Instead, characters'll have defining traits that sorta line up with the D&D alignment scales, but can also be divided into stuff like goals, ideals, etc.
Rather than "always lawful evil" crap, certain cultures (independent from species and race!) will have particular ideals. A person of that culture will have a higher than normal chance of having some of those ideals for their defining traits, but it's by no means guaranteed.
So anyway, other than the points highlighted above, what I most need help on right now is magic. I'm going to add a post at the end of this thread summarizing the current magic system, to bump it up.
Hi, new member here, but I've played a bit of D&D and other RPGs, and been a reader of OOTS for awhile. But I've never really gotten into RPGs so much, because pretty much all of the systems have annoying rules and inconsistencies (many of which have been lampooned on OOTS). So I've been working, on and off for the past years or two, on my own RPG system. There'll no doubt be some annoyances and inconsistencies inherent to this one, but I hope to make it simultaneously more streamlined and more "realistic" than the other systems out there.
Any suggestions, advice, and other help would be welcome. Even if it's just to give up. I've been sorely tempted to, many times in the past.
Even though I have very very little done on this (compared to an actual, complete RPG system), this post is a real doozy, so be warned.
Anyway, this is a system that operates on some different paradigms from most of the RPGs I've played, and hopefully has a more logical way of doing things. It's also a pure percentile system, since almost everyone intuitively understands percentages, and will be able to grasp "you have a 50% chance" more readily than "you have to roll an 11 or higher with a 20-sided die."
Just an example of the way I've been looking at this, in terms of both "realism" and playability, is the problem of hit points. Hit points = physical integrity makes no sense in D&D. Real people, at least, don't gain the ability to take more damage, with experience. If you get stabbed in the heart, you're probably going to be dead soon, no matter what level you are.
Conventional HP really appear to be something like a cross between subdual damage and character skill. An attack that would stagger a novice, or even kill them outright, is no problem to a high level hero, who knows all the tricks of rolling with the blow, or absorbing it on the strongest portion of their armor, or deflecting it at the last minute so it does less damage.
But then you've got all kinds of strange quirks and things. Like healing. Apparently, different level characters take different amounts of actual physical damage from the same attack, yet healing spells heal the same number of points. And a character still has all their extra HP if they're naked; at least some of that damage-taking ability has to come from armor, for most character classes. All kinds of weird things like that stem from having HP as the primary defensive stat.
So let's say HP represent actual physical damage. A high level character will have only marginally more HP than a low level one, since they both bleed just as easily. So how should the reduction in damage be reflected? The most elegant system I've been able to devise combines the damage roll and the to hit roll. You have to roll under a number to hit, so at low % chances to hit, you also do reduced damage.
The more you think about it, the more it makes sense (at least to me). An utterly unskilled person, flailing about blindly, is very unlikely to do very much damage (to the other person, anyway) unless they get lucky (critical hit). Likewise, someone very skilled at evading blows should also be skilled at lessening their severity, if only by virtue of trying to out of the way, and thus rolling with the blow; or failing to totally deflect it, but still reducing the strike's effectiveness. So in this system, your % chance to hit also equals the maximum % of the weapon's base damage you can do.
The main problem is that calculating damage becomes very annoying, unless everything is expressed in D100s. And that's one of my main issues with GURPS. Every single darn weapon doing Xd6 gets old fast. But having to whip out a calculator every time you hit would get old even faster.
And yet, combining those rolls solves so many problems. Like critical hits. Nothing is worse than going "Yeah! Natural 20, baby! Double damage! [die rolling noise] Aw, man, 1! So I do... 2 damage. Great. Some critical." In this system, if you roll a critical, you get 100% damage gratis, then roll again, and whatever % you get is added. So even if you manage to roll a natural 1% the second time, at least you still do 101% damage.
It also reflects skill differences quite adequately. Only being able to do 10% base damage when you've got a 10% chance to hit may seem ridiculous, but think of a similar situation in D&D. If some guy in plate armor is so much more skilled than you that you have to roll a 19 or 20 to hit him, would your dinky little 1d8 longsword be anything more than a nuisance to him anyway, even if you do hit repeatedly?
AC bonuses due to size are a bit different, but 10% of the base damage of any respectable weapon would be enough to kill a mouse or pixie or something, when you consider that now HP actually do represent physical damage. A relatively minor wound to a human could easily kill a small animal. I've tentatively decided that pounds of body mass should equal hit points, since, ah... "heavy" people actually do have more blood in them, and are potentially harder to injure, due to their natural "armor." Of course, they'd also have penalties to agility and such.
So it's a very elegant system in many respects, but very awkward when it comes time to actually calculate the damage. It'd be perfectly suited to a CRPG, though, since the computer could take care of all the grunt work. Best idea I've been able to come up with is to just make it so that damage is calculated in 10% increments. If you roll a 1-10 (and it hits), you do 10% damage, 31-40 does 40%, etc. As long as all damages are multiples of 10, that's simple enough. The inventory sheet could even have a spot where you can write the damage your weapon does at different die rolls.
Another, cruder alternative might be to just have vague damage magnitudes, like in Silhouette, but I like that even less than all damages being expressed in Xd100.
Then we've got weapon skills. D&D, GURPS, and every other system I'm vaguely familiar with all have the same problems. They're either too specific, or too general. Like Fallout GURPS only has the following combat skills: small guns, big guns, energy weapons, unarmed, melee weapons, and thrown. That's it. So if you can shoot a pistol well, you can shoot a shotgun equally well (as both are "small guns;" "big guns" refers to things like miniguns and heavy artillery), but not a laser pistol. Yeah, that totally makes perfect sense.
Standard D&D is just as bad, in the opposite way (at least the last time I played, which was, admittedly, quite awhile ago). If you're skilled in, say, the longsword, you must use a longsword to get that skill bonus. If you suddenly find yourself with a bastard sword, the extra few oz. of weight and inches of handle suddenly make you as clumsy and helpless as a child.
Best way I've been able to address that is to have weapon skills broken into several broad categories. For Melee weapons, it's:
1. Size. Weapons can be Very Small (daggers, blackjacks), Small (machetes, shortswords, and the like), Medium (the majority of medieval-style weapons), Large (sledgehammers, greatswords, and the like), or Very Large (mostly spears and staves). The general distinction between Medium and Large weapons is that Medium ones can be comfortably weilded with one hand, while Large ones require two hands.
2. Balance. Needs a better name. Handling? Something like that. Basically, you've got weapons that are heavier at the end that you whack the other guy with (like maces, hammers, and axes), weapons that are heavier at the end you hold (like most cut and thrust swords), weapons that balance around the middle (like falchions, many cavalry sabers, and plain old sticks), and then there's flexible weapons (like chains, flails, and things).
3. Type. Definitely needs a better name, but I've no ideas. Edged, pointy, blunt, and spiked. Whether you use your Edged or Pointy skill with a sword or knife depends on whether you're cutting or stabbing with it. Obviously, you want to hit someone with a stick differently than with a sword, to inflict the maximum possible damage.
4. Individual. This is a "write-in" skill where you put the specific weapon you specialize in. So if you specialize in the English longsword, and suddenly find yourself with a katana or whatever, you can use the other 3 skills, but not this one. On the other hand, if you have a jian instead, you may be able to use some of the Individual skill. I'm thinking a small bonus if using a favorite weapon (as in, a specific individual weapon), base stat if using a weapon of the general class that you specialize in, and a small penalty if it's fairly similar. Actual numbers are up in the air until I can get some playtesting done, which is far in the future for now.
Each of the skills caps at 100%. So you can have a maximum of a 400% (plus the Familiar Weapon bonus) chance to hit, under optimal conditions. Which means every hit (under optimal conditions) would be a supercritical, doing several times the weapon's base damage. Naturally, the skill system will have to be that higher levels of skill are harder to attain. I'd need to hammer out the specifics of the XP system before coming up with anything concrete, but I'm thinking that individual skills up to 25% should be easy to attain (since anyone can whack a tied up person or something 100% of the time), but quickly become more difficult after that.
I'm thinking something like 100% is just basic competence, 200% is mastery as far as mere mortals are concerned, and 300% and beyond require inordinate amounts of training and experience.
Projectile weapon skills and unarmed are almost totally undeveloped, for now. A system with the same 3-generic-skills-plus-a-specific-one theme is obviously called for.
Armor class is fairly well developed. You have 3 categories this time, and no individual category.
1. Evade. Pretty self-explanatory. Heavy armor should reduce this skill, but not below 0. So a heavy armor user may never bother to put any points here.
2. Block. Also self-explanatory. I don't think I'll make any distinction between blocking with a shield or a weapon, as far as the skill goes; having a shield will just add to your Armor.
3. Armor. Derived entirely from the armor you're wearing.
Given that the most protective armors will also reduce your evasiveness, AC would probably effectively cap at less than 300%. And critical hits will still go through, of course.
Finally, special abilities and such. I personally don't really care for the addition of feats in D&D, and I don't think something like that'd work in this system. Instead, there may be "secret techniques," which could either be learned (after doing some quest, proportional in difficulty to the effectiveness of the technique), or an intelligent enough character could come up with their own secret technique (incentive for Fighters to not use Intelligence as their dump stat!).
One that I plan on implementing is based on the real-life Meisterhauwen. If you and your opponent are both armed with two-handed cut-and-thrust swords, and yours has a functional short edge (the "back edge"), and your opponent is lightly armored or less, combat is resolved differently. Add up your two-handed sword skills (large, hand-balanced, edged, 2-hand sword), and subtract your opponent's skills divided by two. So if you're fighting someone of equal skill, you end up with 50%. This is your chance of automatically winning the combat (by either disarming the opponent or killing him, at the player's choice), every round/turn/whatever (that's still up in the air). If you fail, you just roll as usual. Very powerful, as long as you're mostly fighting people with crappy armor. And acquiring this skill would require a very difficult quest.
Noncombat skills are still pretty much undeveloped. There's so much crap a character could possibly learn, I think it would be easiest to have _all_ non-combat skills be write-in. But most characters would require a trainer, or at least a book or something, to even get a skill onto their character sheet, making noncom skills campaign-based. But a sufficiently intelligent character may be able to teach themself a skill. Which would require a bunch of rules for how high intelligence needs to be for each skill. And if someone desperately wants to learn Chicken Juggling... I guess it'd be up to the GM's discretion.
Which brings us to stats. I've decided on the following:
strength
perception
stamina
constitution
agility
dexterity
intelligence
wisdom
willpower
charisma
Stat magnitudes haven't been decided on yet. I guess 1 to 100 could represent the human norm, to make rolling stats easier, with small animals and things having negative numbers? I dunno.
Pretty similar to D&D, but a couple stats are broken up. Perception is seperate from wisdom, willpower from charisma, agility from dexterity. Most of the stats are obvious, but some need some explanation.
Perception is seperate, because it's quite possible to be wise to the ways of the world, and still be utterly oblivious to what's actually happening around you. Perception represents general awareness of one's surroundings, more than actual acuity of the senses (though that is also a factor). "AWareness" may also be a good stat name.
Stamina represents actual physical fitness; the ability to keep on running, fighting, and casting spells when lesser men would have collapsed from exhaustion. Constitution is more like toughness and resistance to damage, whether it's from being in excellent shape, or from having a layer of blubber.
Agility represents whole-body agility, combined with speed. Dexterity is more like manual dexterity; hand-eye coordination, and ability to do precision work. A concert pianist who trips over his own feet all the time would have low agility and high dexterity. A lightning-fast rogue who can evade any blow, yet struggles to tie her shoes, would be the opposite.
And charisma is basically just physical attractiveness combined with people skills.
Nothing more concrete than that, yet.
Finally, magic. This is what I think is the most original aspect of this system. I spent quite awhile thinking of a plausible way that magic could actually work, instead of "it just does." My best idea thus far is Probability Manipulation.
I like to describe it as like the "bowling dance," except it works. Everyone's seen the "bowling dance," if only on TV. You throw the ball, then start to gyrate and gesticulate wildly, trying to somehow get the darn thing to roll in a different direction. It's also fairly common in golf.
Many physical processes are random; it's just the scale that makes them predictable. Let's say you've got a perfectly formed coin that is precisely weighted to favor neither heads nor tails, and a perfectly random machine to flip it for you. The chances of getting either heads or tails is precisely 50%. If you flip the coin only 2 times, you've got a 25% chance of two heads. But if you flip it 4 times, it drops down to 6.25%. If you flip 4 million times, your chances of all heads is basically nonexistant. Any substantial imbalance at all is very unlikely. You're almost guaranteed to get nearly equal numbers of heads and tails.
Many other things work about the same way. If you put a single cold molecule in a box with 3 hot ones, it may stay cold for a very long time, because there will be very few interactions, and each one is random. Every time a hot molecule hits the cold one, chances are good that the cold one will absorb heat, but it's not guaranteed. It's even possible that the cold one will transfer heat to the hot one! In the long run, the 4 molecules will equalize in temperature, but some minor manipulation of probability could prevent that from ever happening, or even make the cold molecule colder with time!
If you put a frosty mug of mead in a hot room, it's the same principles, but on a colossally greater scale. You'd have billions of interactions between the air, the mead, and the glass every second. But if probability could be changed, so that the air and glass molecules tend to take heat away from the mead, rather than adding heat, the mead could stay cold indefinitely, even become colder over time.
That's how magic works in this system; through sheer force of will, the probabilities of various subatomic interactions are changed, in order to produce a result. Naturally, magicians in a medieval-type fantasy setting would not understand this, much like ancient people didn't understand the significance of using various herbs to treat illnesses and things.
Magic through probability manipulation is divided into several schools. For now at least, they're heat, Brownian motion, electricity, chemical reactions, and entropy. Like everything else with this ridiculous system, they need better names.
Now, those of you who are more versed in physics may say "wait, at that scale, heat is Brownian motion!" And you're right. But in this case, "heat" magic mostly deals with transfers of heat, while "Brownian motion" is more the direction the particles move. "Heat" is magnitude, "Motion" is vector, in other words. Heat magic can heat or cool things, while Motion magic can create gusts of wind or waves from nowhere.
Entropy magic is a slightly tricky one, but I'm thinking it could be used to heal wounds and repair equipment, by reducing entropy. You could almost think of it as a form of localized time travel, since time can be measured by the progression of entropy. Using it to inflict wounds, however, would be much more difficult, nearly impossible. Increasing entropy into the equivalent of a disintigration spell would be like reducing it until a person is turned into a few lumps of coal or diamond, a bit of metal, and a few clouds of gasses; basically the same effect.
Given the pseudo-time travel nature of magical healing, it may also be somewhat plausible that when a wound is healed, you experience it all over again, so that magical healing is just as painful as being wounded in the first place, and does subdual damage equal to what's being healed. Heal too much in the middle of combat, and you pass out from pain. Even for characters with a high pain threshold, it's still distracting.
Personally, I find standard, consequence-free magical healing too overpowered. Now, that's far from the case in many actual campaigns, but that's because those campaigns are designed around the concept of consequence-free magic healing!
Finally, one very interesting concept for magic is that of invocation vs. evocation. The Wuxia fantasy genre (Chinese chivalric fiction; the Oriental equivalent to Occidental swords 'n sorcery; stuff like Crouching Tiger, Hidden Dragon, and House of Flying Daggers) is pretty well unrepresented in mainstream RPGs. With invoking magic as well as evoking, both types of fantasy could coexist in one game.
For instance, an evoker could use heat and chemical magic to create fireballs, electrical magic to create lightning bolts, and motion magic to create buffeting winds as powerful as a physical blow, to assail her foes. An invoker, on the other hand, could use electrical and chemical magic to speed up nerve impulses (including in the brain) and empower muscle contractions to have superhuman reflexes and strength, and use motion magic to speed up their movements, and even lighten their body (by causing every single particle in their body to tend to try and move up, rather than in some random direction) to the point where they could fly. Eastern and Western chivalric fiction existing side-by-side in the same system could prove very interesting.
The final form of probability manipulation is the most powerful one. Influencing actual rolls in the game. Needs a name, again. Let's just call it Will for now. Will, I would consider different from "magic," in that it's a subtle effect changing everything a character does. Will should be inherent to anyone with magical ability, but not really improvable through training or other conventional means. Haven't really decided how increasing it should be done. But the ranks will probably be 1%, 2%, 5%, 10%, 25%, 50%, and 100%, with 25% being the most that's ever attainable by players, and should be ridiculously hard to achieve.
But anyway, there are two forms of Will. One, tentatively called Determination, is sort of the equivalent of taking 20. If your % chance of success is equal to or less than your probability skill, then that means you will succeed at least that much. It's kind of hard to explain without an example. Let's say you have Determination up to 5%, and a 5% chance of succeeding at something. If you fail 19 times in a row, then through sheer force of will, your 20th attempt will be an automatic success. But if the 19th succeeds, the 20th will be rolled as normal; it's only for successive failures. Or successive successes, if you want the roll fail (like if you're messing with an opponent's roll, rather than your own).
The second form of Will simply changes any roll affecting your character (including opponent's rolls, if they're attacking you, or if the roll otherwise directly affects your character) by up to your Will score. This could get overpowered quickly if not balanced. Definitely needs some playtesting once everything's hammered together, but I'm thinking that 2% would be a fair starting point for beginner characters.
For usage, you can use a will ability one rank below yours as much as you want, equal to your rank once per day, and 2 ranks above once per year. So with the standard 2%, you can do 1% as much as you want, 2% once per day, and 10% most likely only one time in the whole campaign.
How common magic is would be campaign-dependent, but in the one I'm working on now, only a very small number of the populace have any probability manipulation ability, and are at the top of the social heap.
That's about all I have so far. Still needs a ton of fleshing out.
My first campaign (which will probably use these rules, unless I'm talked out of developing them) is further along, but that'll have to wait for another post. My fingers hurt.
Okay, I've spoiler tagged the old post for archival purposes. I'm still working on an in-depth writeup of the rules which are finalized, so I'll just go over the highlights. Actual set rules will come eventually.
I've decided to call it the RGP system. Officially, it stands for Realistic Gaming Platform. But you can call it Role Gaming Play if you want. :smallbiggrin:
General:
There are ten statistics.
Strength - pretty self-explanatory.
Perception - general awareness level in addition to sensory acuity.
Constitution - physical toughness, immune system strength, etc.
Stamina - pretty self-explanatory.
Agility - whole body agility and speed. Running obstacle courses, gymnastics, walking on a narrow beam, etc., rely on Agility.
Dexterity - hand-eye coordination and fine motor control. Playing the piano, brain surgery, shooting a gun, etc., rely on Dexterity.
Intelligence - pretty self-explanatory.
Intuition - being able to subconsciously pick up on subtle clues, even if you don't consciously notice them. Something like if your Intuition is high enough, the GM will ask you to make your own whatever check, so that you know something is up. Or maybe for stuff like a Spot check equivalent, you roll vs. Intuition and Per seperately. If you pass the Int check only, you get a general feeling or something, like "being watched," or "bad feeling," or "hidden treasure." If you pass the Per check only, you actually notice the whatever, and where it is, but get no clues as to the real nature of what you see/hear/whatever. If you pass both, you both notice the thingie, and you get some clue as to what it is. And if you pass neither, it was just the wind.
Charisma - physical attractiveness, "emotional intelligence," general people skills, je na sa quois (I can't spell it!), etc.
Willpower - the ability to do unusual, even supernatural, things through sheer force of will.
Hit points are based on physical size. One pound of body weight (for a living earth creature) equals one hit point. A 180 pound human has 180 hit points. (some weapons, like elephant guns, do more damage to larger creatures)
Your character's ideal weight is based on their stats. Racial base weight plus strength, plus constitution. The best way to gain hit points is to put points into strength and con (see advancement, below).
Your weight can also change based on how much you eat (there will be set rules, but the vast majority of players will simply declare that they eat the normal amount to maintain their ideal weight, and be done with it).
Losing a lot of weight due to malnutrition penalizes Strength and Constitution by the amount you lose (but eating sufficient food later will restore most or all of your Str and Con, depending on how severely you starved). Always pack enough food!
If you become fat, you get penalized for Agility and Stamina, to the point where if you exceed about 500-600 pounds (for a human), you're basically unable to walk under your own power (maximum mobile weight depends on stats). You do get the extra hit points, though; weight in pounds = maximum hit points. In a modern day type campaign, where food is plentiful and you can get a car and a gun, minor obesity isn't so much of a disadvantage. The extra hit points may be worth it depending on your skills.
When your hit points reach zero or below, your stats are all halved. You can go down to a negative score equal to your Willpower before there's a risk of passing out. Gotta roll vs. Willpower every turn to stay conscious.
If you go down to a negative equal to your maximum HP, you gotta roll vs. Willpower or die.
For simplicity, you can make it so that normal NPCs just collapse unconscious or dead when they reach 0 HP. Most NPCs will have an atrocious Will score anyway.
Combat skills:
The attack roll is a percentile (D100) roll. You must roll under your % chance to hit to score a hit.
The attack roll is also the damage roll. The number you get (rounded up to the nearest 10%) is the % of base damage you do. Base damage is weapon-dependent (also strength, when appropriate).
Because your % chance to hit caps the damage you can do, unskilled opponents will fall quickly and not hurt you much, even if they have about the same number of hit points and the same weapons and armor as you.
In the included campaign, weapons do pretty realistic amounts of damage. One or two good, 100% base damage hits with most weapons will be enough to incapacitate most people.
Weapon skills are broken into 3 categories with 4 skills in each one, and then a 4th "write-in" skill. For a given weapon, you use one skill from each category, plus your write-in skill if you have it.
For melee, the skills are Size (Tiny, Small, Medium, Large), Balance (Tip, Middle, Hand, Flexible), Type (Edged, Pointed, Spiked, Blunt).
I really suck at naming stuff! Name suggestions for skills and stuff are always welcome!
So for example, the longsword uses Medium Size, Hand Balance, Edged or Pointed types (depending on if you're chopping or stabbing), and "Longsword" write-in skills.
A katana, on the other hand, uses Medium, Middle, Edged, Katana. Thus someone who has exclusively trained with the longsword, if forced to use a katana, would be able to use their Middle and Edged skills, and weild a katana about half as well as a longsword.
Because of the write-in skill, a generalist can never be as skilled as a specialist.
The cap for each skill is 100%, so your max base chance to hit is 400%.
Defense skills'll be similar, still working on 'em.
Still working on refining ranged combat skills, too. So far the tentative system is Release (Dynamic, Static, Fast Trigger, Slow Trigger), Velocity (Low, Medium, High, Instant), Form (Thrown, Bow, Pistol, Longarm).
Unarmed has got me stumped, need ideas.
At percent chances to hit over 100%, you always hit. You roll, then add your chance to hit over 100% to whatever you rolled. So at a 115% chance to hit, if you roll 45, then you do (45 + 15 round up) 60% base damage.
Critical misses and hits occur when you roll a 0 for your second digit on the attack roll (multiples of 10). Whether it's a critical hit or critical miss depends on whether you hit or missed.
Severity of the critical hit or miss depends on how high or low you rolled. A critical miss at 90 would be rather minor, while a critical hit for 90 should be pretty good. A critical hit at 10 is nothing special, but you gotta be really drunk to miss if you roll a 10, so a critical miss at 10 is pretty bad.
For a critical hit, you take the % you rolled, add it to your % chance to hit for that attack, round up, and there's the damage you do. So if you've got a 65% chance to hit and roll 40, you do 110% base damage.
Thus, critical hits always do more damage than a regular attack, even if you just roll 10. None of that double damage and then you roll a 1 crap.
00 (or 100) is always a critical hit, and always does +100% damage. Ouch. Fortunately, PCs are immune to critical hits, except from boss-level encounters.
Critical misses cost you action points on the next turn, and lower number ones may cause you to hit yourself or something (effect table maybe?).
General combat:
It's an action point + movement point system. One turn is 2 seconds. An average human will have about 10 action points and 10 movement points per turn.
One movement point will let you walk 1 foot, run 3 feet, or sprint 5 feet (if you sprint, it takes several movement points to stop when you're done).
Using one type of point also uses up the same number of the other one, unless you use both simultaneously (need to explain better!).
I.e., you have 8 movement points and 10 action points. You have a laser pistol that takes 5 action points to fire. You can shoot the laser pistol twice, without moving. You can use 5 movement points to move, then shoot once. You can shoot once, then use 3 movement points to move. You can use 8 movement points to move, while simultaneously shooting twice, but at a stiff penalty to accuracy due to moving while shooting.
Armor. A given set of armor will have a percent coverage rating (with %s given for each general area of the body, for calculating partial sets and stuff).
Take your coverage %, round down, divide by ten. A hit roll ending in that number or less hits armor (if it hits at all).
Because of the rounding down thing, an armor has to have true 100% coverage to protect against critical hits. Power armor, magically reinforced armor, forcefields, something like that. True 100% coverage is also required to protect against some special types of damage, like blast/concussive damage from explosives.
Attacks that hit armor are reduced by some % (subtract it from your roll and round up), based on type of damage. Slashing (draw cuts, like slicing, as opposed to hacking), hewing (chopping), piercing, blunt, and ballistic. If it reduces the % to zero or less, no damage is done.
Some weapons will do multiple damage types. You always use the most advantageous damage type, for everything, in that case. So it may be one type for one thing, another type for another.
Example. So let's say you attack some dude with 85% coverage armor, and you have a 60% chance to hit. His armor has 50% reduction vs. the damage type your weapon does. You roll a 58. It hits, but hits armor, so you do (58 - 50 round up) 10% base damage. Then you roll a 39. It hits, and you manage to nail an exposed area, so 40% base damage.
So a single roll tells you whether you hit, whether it was a critical, how good/bad of a critical it was, whether the attack is affected by armor (if you hit), and the amount of damage you did (if hit). Only additional roll would be on an effect table if you get a really good critical hit or really bad critical miss.
Non-Combat skills:
Trying to get a 3 category, 4 skills in each, plus a write-in thing here, too.
Currently, best I've come up with is Background (Social, Mechanical, Survival, Abstract), Scale (Mental, Fine, Gross, Environmental), Sense (Awareness, Touch, Kinesthetic, Emotion).
There's probably a lot of room for refinement there, need ideas!
Advancement:
No levels.
Doing difficult stuff (including training/practice) gives you experience points that can be put towards a relevant skill or stat.
Increasing a skill or stat by one requires the goal skill/stat level squared char points. So going from 59 to 60 requires (60^2) 3600 points.
Just training or practice gives you 1 XP per minute. So reaching 100% in some skill (25% each in four skills) requires 1.5 months of intensive training (8 hours per day), or 1 year of casual training (around an hour a day). Reaching 400% in some skill requires 8 years of intensive training. About right for some insane martial arts guru or whatever. Gains through actual real world experience are much faster, obviously.
Need equations for combat experience and junk.
If trying to transfer stuff to/from D20, one D20 XP equals about 20 RGP XP.
For increasing stats, the maximum you can increase any stat to is double your starting stat, or double your starting intelligence, whichever is higher.
IQ should never be your dump stat. Intelligence is easily the most important stat there is. "Work smarter, not harder" is a reality. Having a high strength score is a combination of both physical brawn, and knowing how to use your strength most effectively and efficiently. Even the strongest person can throw out his back if he doesn't know the best way to lift, stuff like that.
Going to have something similar to feats, except they have to be learned from like, a guru on a mountain or whatever, so they're campaign dependent.
Players will also be able to make their own "feats," and even teach them to others, but how good they are depends on IQ. Once again, IQ is probably your most important stat, regardless of your playings tyle.
Misc:
Alignment in the D&D sense won't exist.
Instead, characters'll have defining traits that sorta line up with the D&D alignment scales, but can also be divided into stuff like goals, ideals, etc.
Rather than "always lawful evil" crap, certain cultures (independent from species and race!) will have particular ideals. A person of that culture will have a higher than normal chance of having some of those ideals for their defining traits, but it's by no means guaranteed.
So anyway, other than the points highlighted above, what I most need help on right now is magic. I'm going to add a post at the end of this thread summarizing the current magic system, to bump it up.
Hi, new member here, but I've played a bit of D&D and other RPGs, and been a reader of OOTS for awhile. But I've never really gotten into RPGs so much, because pretty much all of the systems have annoying rules and inconsistencies (many of which have been lampooned on OOTS). So I've been working, on and off for the past years or two, on my own RPG system. There'll no doubt be some annoyances and inconsistencies inherent to this one, but I hope to make it simultaneously more streamlined and more "realistic" than the other systems out there.
Any suggestions, advice, and other help would be welcome. Even if it's just to give up. I've been sorely tempted to, many times in the past.
Even though I have very very little done on this (compared to an actual, complete RPG system), this post is a real doozy, so be warned.
Anyway, this is a system that operates on some different paradigms from most of the RPGs I've played, and hopefully has a more logical way of doing things. It's also a pure percentile system, since almost everyone intuitively understands percentages, and will be able to grasp "you have a 50% chance" more readily than "you have to roll an 11 or higher with a 20-sided die."
Just an example of the way I've been looking at this, in terms of both "realism" and playability, is the problem of hit points. Hit points = physical integrity makes no sense in D&D. Real people, at least, don't gain the ability to take more damage, with experience. If you get stabbed in the heart, you're probably going to be dead soon, no matter what level you are.
Conventional HP really appear to be something like a cross between subdual damage and character skill. An attack that would stagger a novice, or even kill them outright, is no problem to a high level hero, who knows all the tricks of rolling with the blow, or absorbing it on the strongest portion of their armor, or deflecting it at the last minute so it does less damage.
But then you've got all kinds of strange quirks and things. Like healing. Apparently, different level characters take different amounts of actual physical damage from the same attack, yet healing spells heal the same number of points. And a character still has all their extra HP if they're naked; at least some of that damage-taking ability has to come from armor, for most character classes. All kinds of weird things like that stem from having HP as the primary defensive stat.
So let's say HP represent actual physical damage. A high level character will have only marginally more HP than a low level one, since they both bleed just as easily. So how should the reduction in damage be reflected? The most elegant system I've been able to devise combines the damage roll and the to hit roll. You have to roll under a number to hit, so at low % chances to hit, you also do reduced damage.
The more you think about it, the more it makes sense (at least to me). An utterly unskilled person, flailing about blindly, is very unlikely to do very much damage (to the other person, anyway) unless they get lucky (critical hit). Likewise, someone very skilled at evading blows should also be skilled at lessening their severity, if only by virtue of trying to out of the way, and thus rolling with the blow; or failing to totally deflect it, but still reducing the strike's effectiveness. So in this system, your % chance to hit also equals the maximum % of the weapon's base damage you can do.
The main problem is that calculating damage becomes very annoying, unless everything is expressed in D100s. And that's one of my main issues with GURPS. Every single darn weapon doing Xd6 gets old fast. But having to whip out a calculator every time you hit would get old even faster.
And yet, combining those rolls solves so many problems. Like critical hits. Nothing is worse than going "Yeah! Natural 20, baby! Double damage! [die rolling noise] Aw, man, 1! So I do... 2 damage. Great. Some critical." In this system, if you roll a critical, you get 100% damage gratis, then roll again, and whatever % you get is added. So even if you manage to roll a natural 1% the second time, at least you still do 101% damage.
It also reflects skill differences quite adequately. Only being able to do 10% base damage when you've got a 10% chance to hit may seem ridiculous, but think of a similar situation in D&D. If some guy in plate armor is so much more skilled than you that you have to roll a 19 or 20 to hit him, would your dinky little 1d8 longsword be anything more than a nuisance to him anyway, even if you do hit repeatedly?
AC bonuses due to size are a bit different, but 10% of the base damage of any respectable weapon would be enough to kill a mouse or pixie or something, when you consider that now HP actually do represent physical damage. A relatively minor wound to a human could easily kill a small animal. I've tentatively decided that pounds of body mass should equal hit points, since, ah... "heavy" people actually do have more blood in them, and are potentially harder to injure, due to their natural "armor." Of course, they'd also have penalties to agility and such.
So it's a very elegant system in many respects, but very awkward when it comes time to actually calculate the damage. It'd be perfectly suited to a CRPG, though, since the computer could take care of all the grunt work. Best idea I've been able to come up with is to just make it so that damage is calculated in 10% increments. If you roll a 1-10 (and it hits), you do 10% damage, 31-40 does 40%, etc. As long as all damages are multiples of 10, that's simple enough. The inventory sheet could even have a spot where you can write the damage your weapon does at different die rolls.
Another, cruder alternative might be to just have vague damage magnitudes, like in Silhouette, but I like that even less than all damages being expressed in Xd100.
Then we've got weapon skills. D&D, GURPS, and every other system I'm vaguely familiar with all have the same problems. They're either too specific, or too general. Like Fallout GURPS only has the following combat skills: small guns, big guns, energy weapons, unarmed, melee weapons, and thrown. That's it. So if you can shoot a pistol well, you can shoot a shotgun equally well (as both are "small guns;" "big guns" refers to things like miniguns and heavy artillery), but not a laser pistol. Yeah, that totally makes perfect sense.
Standard D&D is just as bad, in the opposite way (at least the last time I played, which was, admittedly, quite awhile ago). If you're skilled in, say, the longsword, you must use a longsword to get that skill bonus. If you suddenly find yourself with a bastard sword, the extra few oz. of weight and inches of handle suddenly make you as clumsy and helpless as a child.
Best way I've been able to address that is to have weapon skills broken into several broad categories. For Melee weapons, it's:
1. Size. Weapons can be Very Small (daggers, blackjacks), Small (machetes, shortswords, and the like), Medium (the majority of medieval-style weapons), Large (sledgehammers, greatswords, and the like), or Very Large (mostly spears and staves). The general distinction between Medium and Large weapons is that Medium ones can be comfortably weilded with one hand, while Large ones require two hands.
2. Balance. Needs a better name. Handling? Something like that. Basically, you've got weapons that are heavier at the end that you whack the other guy with (like maces, hammers, and axes), weapons that are heavier at the end you hold (like most cut and thrust swords), weapons that balance around the middle (like falchions, many cavalry sabers, and plain old sticks), and then there's flexible weapons (like chains, flails, and things).
3. Type. Definitely needs a better name, but I've no ideas. Edged, pointy, blunt, and spiked. Whether you use your Edged or Pointy skill with a sword or knife depends on whether you're cutting or stabbing with it. Obviously, you want to hit someone with a stick differently than with a sword, to inflict the maximum possible damage.
4. Individual. This is a "write-in" skill where you put the specific weapon you specialize in. So if you specialize in the English longsword, and suddenly find yourself with a katana or whatever, you can use the other 3 skills, but not this one. On the other hand, if you have a jian instead, you may be able to use some of the Individual skill. I'm thinking a small bonus if using a favorite weapon (as in, a specific individual weapon), base stat if using a weapon of the general class that you specialize in, and a small penalty if it's fairly similar. Actual numbers are up in the air until I can get some playtesting done, which is far in the future for now.
Each of the skills caps at 100%. So you can have a maximum of a 400% (plus the Familiar Weapon bonus) chance to hit, under optimal conditions. Which means every hit (under optimal conditions) would be a supercritical, doing several times the weapon's base damage. Naturally, the skill system will have to be that higher levels of skill are harder to attain. I'd need to hammer out the specifics of the XP system before coming up with anything concrete, but I'm thinking that individual skills up to 25% should be easy to attain (since anyone can whack a tied up person or something 100% of the time), but quickly become more difficult after that.
I'm thinking something like 100% is just basic competence, 200% is mastery as far as mere mortals are concerned, and 300% and beyond require inordinate amounts of training and experience.
Projectile weapon skills and unarmed are almost totally undeveloped, for now. A system with the same 3-generic-skills-plus-a-specific-one theme is obviously called for.
Armor class is fairly well developed. You have 3 categories this time, and no individual category.
1. Evade. Pretty self-explanatory. Heavy armor should reduce this skill, but not below 0. So a heavy armor user may never bother to put any points here.
2. Block. Also self-explanatory. I don't think I'll make any distinction between blocking with a shield or a weapon, as far as the skill goes; having a shield will just add to your Armor.
3. Armor. Derived entirely from the armor you're wearing.
Given that the most protective armors will also reduce your evasiveness, AC would probably effectively cap at less than 300%. And critical hits will still go through, of course.
Finally, special abilities and such. I personally don't really care for the addition of feats in D&D, and I don't think something like that'd work in this system. Instead, there may be "secret techniques," which could either be learned (after doing some quest, proportional in difficulty to the effectiveness of the technique), or an intelligent enough character could come up with their own secret technique (incentive for Fighters to not use Intelligence as their dump stat!).
One that I plan on implementing is based on the real-life Meisterhauwen. If you and your opponent are both armed with two-handed cut-and-thrust swords, and yours has a functional short edge (the "back edge"), and your opponent is lightly armored or less, combat is resolved differently. Add up your two-handed sword skills (large, hand-balanced, edged, 2-hand sword), and subtract your opponent's skills divided by two. So if you're fighting someone of equal skill, you end up with 50%. This is your chance of automatically winning the combat (by either disarming the opponent or killing him, at the player's choice), every round/turn/whatever (that's still up in the air). If you fail, you just roll as usual. Very powerful, as long as you're mostly fighting people with crappy armor. And acquiring this skill would require a very difficult quest.
Noncombat skills are still pretty much undeveloped. There's so much crap a character could possibly learn, I think it would be easiest to have _all_ non-combat skills be write-in. But most characters would require a trainer, or at least a book or something, to even get a skill onto their character sheet, making noncom skills campaign-based. But a sufficiently intelligent character may be able to teach themself a skill. Which would require a bunch of rules for how high intelligence needs to be for each skill. And if someone desperately wants to learn Chicken Juggling... I guess it'd be up to the GM's discretion.
Which brings us to stats. I've decided on the following:
strength
perception
stamina
constitution
agility
dexterity
intelligence
wisdom
willpower
charisma
Stat magnitudes haven't been decided on yet. I guess 1 to 100 could represent the human norm, to make rolling stats easier, with small animals and things having negative numbers? I dunno.
Pretty similar to D&D, but a couple stats are broken up. Perception is seperate from wisdom, willpower from charisma, agility from dexterity. Most of the stats are obvious, but some need some explanation.
Perception is seperate, because it's quite possible to be wise to the ways of the world, and still be utterly oblivious to what's actually happening around you. Perception represents general awareness of one's surroundings, more than actual acuity of the senses (though that is also a factor). "AWareness" may also be a good stat name.
Stamina represents actual physical fitness; the ability to keep on running, fighting, and casting spells when lesser men would have collapsed from exhaustion. Constitution is more like toughness and resistance to damage, whether it's from being in excellent shape, or from having a layer of blubber.
Agility represents whole-body agility, combined with speed. Dexterity is more like manual dexterity; hand-eye coordination, and ability to do precision work. A concert pianist who trips over his own feet all the time would have low agility and high dexterity. A lightning-fast rogue who can evade any blow, yet struggles to tie her shoes, would be the opposite.
And charisma is basically just physical attractiveness combined with people skills.
Nothing more concrete than that, yet.
Finally, magic. This is what I think is the most original aspect of this system. I spent quite awhile thinking of a plausible way that magic could actually work, instead of "it just does." My best idea thus far is Probability Manipulation.
I like to describe it as like the "bowling dance," except it works. Everyone's seen the "bowling dance," if only on TV. You throw the ball, then start to gyrate and gesticulate wildly, trying to somehow get the darn thing to roll in a different direction. It's also fairly common in golf.
Many physical processes are random; it's just the scale that makes them predictable. Let's say you've got a perfectly formed coin that is precisely weighted to favor neither heads nor tails, and a perfectly random machine to flip it for you. The chances of getting either heads or tails is precisely 50%. If you flip the coin only 2 times, you've got a 25% chance of two heads. But if you flip it 4 times, it drops down to 6.25%. If you flip 4 million times, your chances of all heads is basically nonexistant. Any substantial imbalance at all is very unlikely. You're almost guaranteed to get nearly equal numbers of heads and tails.
Many other things work about the same way. If you put a single cold molecule in a box with 3 hot ones, it may stay cold for a very long time, because there will be very few interactions, and each one is random. Every time a hot molecule hits the cold one, chances are good that the cold one will absorb heat, but it's not guaranteed. It's even possible that the cold one will transfer heat to the hot one! In the long run, the 4 molecules will equalize in temperature, but some minor manipulation of probability could prevent that from ever happening, or even make the cold molecule colder with time!
If you put a frosty mug of mead in a hot room, it's the same principles, but on a colossally greater scale. You'd have billions of interactions between the air, the mead, and the glass every second. But if probability could be changed, so that the air and glass molecules tend to take heat away from the mead, rather than adding heat, the mead could stay cold indefinitely, even become colder over time.
That's how magic works in this system; through sheer force of will, the probabilities of various subatomic interactions are changed, in order to produce a result. Naturally, magicians in a medieval-type fantasy setting would not understand this, much like ancient people didn't understand the significance of using various herbs to treat illnesses and things.
Magic through probability manipulation is divided into several schools. For now at least, they're heat, Brownian motion, electricity, chemical reactions, and entropy. Like everything else with this ridiculous system, they need better names.
Now, those of you who are more versed in physics may say "wait, at that scale, heat is Brownian motion!" And you're right. But in this case, "heat" magic mostly deals with transfers of heat, while "Brownian motion" is more the direction the particles move. "Heat" is magnitude, "Motion" is vector, in other words. Heat magic can heat or cool things, while Motion magic can create gusts of wind or waves from nowhere.
Entropy magic is a slightly tricky one, but I'm thinking it could be used to heal wounds and repair equipment, by reducing entropy. You could almost think of it as a form of localized time travel, since time can be measured by the progression of entropy. Using it to inflict wounds, however, would be much more difficult, nearly impossible. Increasing entropy into the equivalent of a disintigration spell would be like reducing it until a person is turned into a few lumps of coal or diamond, a bit of metal, and a few clouds of gasses; basically the same effect.
Given the pseudo-time travel nature of magical healing, it may also be somewhat plausible that when a wound is healed, you experience it all over again, so that magical healing is just as painful as being wounded in the first place, and does subdual damage equal to what's being healed. Heal too much in the middle of combat, and you pass out from pain. Even for characters with a high pain threshold, it's still distracting.
Personally, I find standard, consequence-free magical healing too overpowered. Now, that's far from the case in many actual campaigns, but that's because those campaigns are designed around the concept of consequence-free magic healing!
Finally, one very interesting concept for magic is that of invocation vs. evocation. The Wuxia fantasy genre (Chinese chivalric fiction; the Oriental equivalent to Occidental swords 'n sorcery; stuff like Crouching Tiger, Hidden Dragon, and House of Flying Daggers) is pretty well unrepresented in mainstream RPGs. With invoking magic as well as evoking, both types of fantasy could coexist in one game.
For instance, an evoker could use heat and chemical magic to create fireballs, electrical magic to create lightning bolts, and motion magic to create buffeting winds as powerful as a physical blow, to assail her foes. An invoker, on the other hand, could use electrical and chemical magic to speed up nerve impulses (including in the brain) and empower muscle contractions to have superhuman reflexes and strength, and use motion magic to speed up their movements, and even lighten their body (by causing every single particle in their body to tend to try and move up, rather than in some random direction) to the point where they could fly. Eastern and Western chivalric fiction existing side-by-side in the same system could prove very interesting.
The final form of probability manipulation is the most powerful one. Influencing actual rolls in the game. Needs a name, again. Let's just call it Will for now. Will, I would consider different from "magic," in that it's a subtle effect changing everything a character does. Will should be inherent to anyone with magical ability, but not really improvable through training or other conventional means. Haven't really decided how increasing it should be done. But the ranks will probably be 1%, 2%, 5%, 10%, 25%, 50%, and 100%, with 25% being the most that's ever attainable by players, and should be ridiculously hard to achieve.
But anyway, there are two forms of Will. One, tentatively called Determination, is sort of the equivalent of taking 20. If your % chance of success is equal to or less than your probability skill, then that means you will succeed at least that much. It's kind of hard to explain without an example. Let's say you have Determination up to 5%, and a 5% chance of succeeding at something. If you fail 19 times in a row, then through sheer force of will, your 20th attempt will be an automatic success. But if the 19th succeeds, the 20th will be rolled as normal; it's only for successive failures. Or successive successes, if you want the roll fail (like if you're messing with an opponent's roll, rather than your own).
The second form of Will simply changes any roll affecting your character (including opponent's rolls, if they're attacking you, or if the roll otherwise directly affects your character) by up to your Will score. This could get overpowered quickly if not balanced. Definitely needs some playtesting once everything's hammered together, but I'm thinking that 2% would be a fair starting point for beginner characters.
For usage, you can use a will ability one rank below yours as much as you want, equal to your rank once per day, and 2 ranks above once per year. So with the standard 2%, you can do 1% as much as you want, 2% once per day, and 10% most likely only one time in the whole campaign.
How common magic is would be campaign-dependent, but in the one I'm working on now, only a very small number of the populace have any probability manipulation ability, and are at the top of the social heap.
That's about all I have so far. Still needs a ton of fleshing out.
My first campaign (which will probably use these rules, unless I'm talked out of developing them) is further along, but that'll have to wait for another post. My fingers hurt.