Topic: A Skill System
Started by: Christoffer Lernö
Started on: 8/17/2002
Board: RPG Theory
On 8/17/2002 at 6:33am, Christoffer Lernö wrote:
A Skill System
To avoid cluttering the thread on skills which has so much other interesting stuff than mechanics, I post this independently. Basically it's an attempt at an implementation of the karma->fortune mechanic.
After writing this I realized that the "quality of success" part doesn't take into account "random external circumstances". That shouldn't be too hard to add, but it's obviously not there yet. Just pointing it out in case someone wonders.
Basics
To succeed with an action, basically your rating has to be above the difficulty of the task. Very simple. Your rating is 4 and difficulty is 3. Yes you just succeeded, congrats. Difficulty was 4 or 5? Oh bummer, you just failed.
GM Difficulty Rolling
How is difficulty decided on then? Well, actually unlike most other games it can be random. If you're running soliloquy the GM makes it up. It doesn't have to be the same for every character, so the GM has full freedom to wing it. The GM is ALWAYS allowed to set the difficulty as he or she pleases. Here are some guidelines:
[code]
Difficulty Description
0 Stuff like walking and things
anything that only is difficult
for disabled people
1 This is stuff that might possibly
fail if you suck bad. Like standing
on one leg for 20 seconds
2 Here we're getting to things people
sometimes fail at. Like remembering
where they put their keys.
3 This difficulty covers things an
average person has a 50-50 chance of
succeeding at, like putting together
simple furniture.
4 Now we're coming to things you have
to be skilled to do with any
confidence. Like installing a computer.
5 Here's things even professionals have
difficulty with. If you want to jump
more than 4 meters or discover a
cleverly hidden trap you're searching
for, this is the difficulty.
6 If you're good at something,
you still only have 50% chance of
succeeding at this task.
7 You're very skilled but still have
difficulty with this task. Think
walking on tightrope and stuff.
8 Now we're talking about really crazy
things like bicycling on a tightrope
and stuff.
9 Insanely difficult tasks, like extreme
circus acts and stuff. Don't try this
at home kids.
[/code]
Random
For non-soliloquy play, the GM ought to go for the Random roll. This simulates the varying circumstances. Bob the Eagle-Eyed Ranger might get a difficulty of 8 to spot that ambush because he was distracted by Princess Beauty while Oggo the Troll might have only two because he just happened to look in the right direction at the right time. The GM random die is everything the characters don't really do themselves.
There are two ways of doing the random roll:
1. Capped Random
With capped random you simply roll a die and let that tell the outcome. You can use D4, D6, D8, D10, D12 or even a D20. It's "capped" because it has a maximum outcome. The virtue of this roll is that it lets practically anyone succeed if the circumstances are right. Use this for spotting hidden stuff or anything else that might be random. The higher the value of the dice, the less chance of anyone succeeding. Please note that unless you want some characters to automatically succeed the die max has to be above their basic rating.
2. Minimum Random
Minimum random isn't very different from capped random. What you're doing here is also rolling a die, but you add a modifier, like +1 or +2 or whatever. This gives the effect that you need a minimum stat to have a chance. The size of the die determines how random things are. Like this:
[code]
approx
50-50 of Randomness
rating Small Medium Large Very Large Huge
1 1D4-1 1D6-2 1D8-3 1D10-4 1D12-5
2 1D4 1D6-1 1D8-2 1D10-3 1D12-4
3 1D4+1 1D6 1D8-1 1D10-2 1D12-3
4 1D4+2 1D6+1 1D8 1D10-1 1D12-2
5 1D4+3 1D6+2 1D8+1 1D10 1D12-1
6 1D4+4 1D6+3 1D8+2 1D10+1 1D12
7 1D4+5 1D6+4 1D8+3 1D10+2 1D12+1
8 1D4+6 1D6+5 1D8+4 1D10+3 1D12+2
[/code]
Summary
So to sum it up. Either set the difficulty or roll it up. Done so it can be compared with the player rating to see if there is success or not. More on that later.
Answering a Challenge
Once the player has the difficulty, he/she can check if his/her character succeeds.
LD50, Sure Win and Sure Loss
Ok, why do I call it LD50. LD50 is short for "lethal dose 50%" or in other words, if you drink this much of this poison you have a 50% chance of dying. Now how does that relate to the skills? Well everyone starts with a BASIC RATING (not to be confused with the "rating"). If the difficulty is the same as the BASIC RATING you have a 50% chance of succeeding. Or in other words, you're not sure if you'll make it or not.
If you get this difficulty, you can roll any die and select the upper half to be success and the lower failure. That's how it works. However, what happens if you have a little lower or a little higher?
Well, depending on the situation this might be unambiguous or not. The LD50 situation is ALWAYS ambiguous, but others might be as well:
[code]
(amb = ambiguous, win = sure win, loss = sure loss)
stat - Randomness
difficulty = None a little medium high
-3 loss loss loss amb
-2 loss loss amb amb
-1 loss amb amb amb
0 (LD50) amb amb amb amb
+1 win amb amb amb
+2 win win amb amb
+3 win win win amb
[/code]
Most situations run on none or little randomness, as this should be remembered is ONLY the randomness of the actual character performance and has nothing to do with external conditions.
How are ambiguous situations resolved then? Well, the BASIC RATING gives you a modifier and a die. The die depends on the randomness of the situation. It's calculated like this:
[code]
Randomness Die+Mod
None (BASIC RATING-1)+1D2
A Little (BASIC RATING-2)+1D4
Medium (BASIC RATING-3)+1D6
High (BASIC RATING-4)+1D8
[/code]
Or an example. You have Rating 6 (that's pretty good), which gives you 5+1D2 (usually you don't put that first one down), 4+1D4 and 3+1D6 (D8 case should be rare in any case).
So you might write 6 (4+1D4/3+1D6).
Anyway, how does that relate to the success and stuff? Well let's say the difficulty was 5. If this was a non-random case it's obviously a win since 5+1D2 always beats 5. On the "little random" case you'd have to roll and win on a 2-4. Or "medium random" you'd win on a 3-6. Basically the more random a situation is the more chance of succeeding with a difficult task as well as failing with a simple one.
Depending on the type of task, the randomness should be decided on. Again this is the GM's call. Usually an extended task creates less random results, but that's not ALWAYS the case.
Determining quality, time and other things
Ok, so you jumped that chasm, climbed that wall or whatever. How do you know how well you succeeded? Well you roll. THE SAME DICE+MOD AS FOR THE TEST. Even if you didn't do a test (you succeeded automaticaly maybe), you can roll. Let's say the BASIC RATING for a task was 4 and it was "a little random". Roll then becomes 2+1D4. Rolling a 4 the character succeeded with the task of climbing the wall, but how quick was it?
Sometimes there's not even a matter of success or failure, but about how well it goes. If it's not important, the GM can always narrate it, but it can also be rolled for. You always use the same die as the original roll (if there was one). In our case it was 2+1D4. We roll a 1. That's a 3 and puts it on the lower scale, it means it took more time than usual. If we want to check how good it looked we can roll another 2+1D4 roll to determine that.
However, it should be noted that all of this is only IF the detail is interesting to players or the GM. Otherwise simply treat it as an average success for a character with that certain BASIC RATING. DON'T DON'T DON'T use it in the general case.
Arbitrary levels of detail
If you're looking at very high detail, let's say there's a long jumping contest and you want to see who wins, the 2+1D4 might not suffice. In that case, keep rolling as many extra D4 as you win, with everyone becoming a sequential digit. Like this:
[code]
2+1D4=1 quality=3
1D4=3 quality=3.3
1D4=2 quality=3.32
1D4=4 quality=3.324
and so on
[/code]
This way abitrarily detailed performance can be created. Note that the digits only use the random die and not the modifier.
Going for better than average at a cost
You can also go for a better than average result in one aspect at the expense of other aspects. One example would be to give extra time for the task and so on.
Basically it works like this: The stuff you want advantage with you get to roll two of the random dice and pick the highest, and for everything else (or just at certain aspects, it's up to the GM) you roll two dice and pick the lowest.
For example, using a good running start might give two dice instead of one for jumping that chasm. Or writing that book at full speed you might get 2 dice for deciding on how fast it's finished, but 2 dice pick the worst for contents and how readable your writing is. Ultimately it's up to the GM to decide on the advantage (it can be more than 2 dice) and disadvantage in each situation.
When the player has announced the character is doing something obviously helpful to succeed with something before difficulties are determined by the GM. For example the Ranger declares he's looking for ambushes right now, just before the GM was gonna roll for difficulties for detecting ones, he should assign a lower difficulty for that player in case of assigning difficulties, or roll two dice pick the lowest in the case of rolling for difficulties. In the opposite case, of someone doing something distracting the GM might use roll two dice pick the highest.
Summary
Ok, that about covers the system.
For the GM there are four dials.
1. Difficulty die
2. Difficulty mod
(or 1-2 decide on difficulty)
3. Randomness of player rolls
4. Advantages/Disadvantages (several dice, pick lowest or highest)
Players can change their chances by paying for Advantages with Disadvantages.
Quality and other parameters are rolled independently of any success roll. They can use any detail by way of the digit system.
Something like that.