The Impossible Dream
Resolution Mechanics I
by Hunter Logan
Resolution Mechanics I The
Impossible Dream Installment #4
by Hunter Logan
Thus far, I have talked about play flow,
balance of power, and player goals. This time, I want to move on and talk
about something near and dear to most every designer's heart: Resolution
are the means for getting things done
in the game. When a character searches a room, attempts to run the gauntlet,
or negotiate a contract, resolution mechanics determine what happens. This
is a monster topic, so I will present it in two parts. The first part will
cover the Three Means of Resolution.
The Three Means of Resolution
The Three Means
of Resolution are loosely based on Jonathan Tweet's three means of
resolution as presented in the Everway RPG
and as modified
by Ron Edwards in his many RPG theory discussions. Tweet's terms are Drama,
Fortune and Karma. Edwards also uses them, though he applies slightly
different meanings. I mention Tweet's terms as reference, but I've got my
own take on them. To avoid the great onus and inertia of history, I'm not
using them. I'm using the terms Chance, Ability and Intent. This is the way
I conceptualize the Three Means.
is random determination of what happens. Roll dice,
draw cards, flip coins, and look at the results. They are random and subject
to the laws of statistics. Dice are a common and popular method of
generating random results in RPGs. I like dice because all dice have similar
characteristics in the way they generate numbers. Here are some examples.
- A single die generates a linear curve. Roll a d20 and you have a
flat 5% chance of rolling any particular number. You have the same chance of
rolling a 1 as you do a 10 or a 20. When you change the number of sides on
the die, you change the flat percentage chance and the range. Roll a d12 and
you get a range from 1 to 12 with an 8% chance of getting a particular
result. Roll a d10 and the range is 1 to 10 (or 0 to 9) with a 10% chance of
getting a given result. Roll a d8 and the range is 1 to 8 with a 12-1/2%
chance of getting a given result and so on.
- If you roll several dice and
evaluate the result on each die independently, the curve for each die is
- Rolling a pair of dice and adding the results
generates a bell curve. For example, you may roll two 6-sided dice and add
the results. This produces a range of results from 2 to 12. At the extremes,
the player has about a 6% chance of getting a 2 or a 12. In the middle, he
has about 17% chance of rolling a 7. The actual result is random, but the
player has a 28% chance of rolling 2 to 5, a 44% chance of rolling a result
from 6 to 8, and a 28% chance of rolling 9 to 12. Clearly, the middle is
- Rolling a pair of unequal dice also generates a bell
curve. Rolling a d6 and a d4 and adding the results produces a range from 2
to 10. At the extremes, the player has about an 8% chance of rolling a 2 or
a 10. In the middle, he has about 20% chance of rolling a 6. He has about a
23% chance of rolling 3 to 4, a 54% chance of rolling a result from 5 to 7,
and a 23% chance of rolling an 8 to 10. Again, the middle is favored.
- As you roll more dice and add the results, the bell curve becomes
flatter at the top with a greater chance of generating an average value and
a far smaller chance of generating an extreme value. Rolling 3d4, for
instance, produces a range from 3 to 12. A player has about a 3% chance of
rolling either a 3 or a 12, a 15 % chance of rolling 3 to 5, a 69 % chance
of rolling from 6 to 10, and a 15 % chance of rolling 10 to 12. Again the
middle is strongly favored with a 1-in-3 likelihood that the player will
roll either a 7 or an 8.
- Dice can be manipulated to tailor
- Curved Results: The
player rolls dice, but the actual result is curved. For example, the
designer may have the players roll a single d10, but the die roll may
actually produce results from φ3 to +3. Here's one way it could
|Die Roll||Result |
- Exploding Die Roll: The player rolls the dice and rolls
again on a designated result. The result of the next die roll is added to
the first. For example, the player rolls a d6. On a 6, the die "explodes."
The player rolls the d6 again and adds the result to his total. So, the
player could roll a 6 then roll a 4 to get 10.
If the die roll is open-ended, this goes on as long as the player's die
rolls meet the condition for explosion. A player might roll 6, 6, 6, 6, 2
and get 26 off the die roll.
If the die roll is closed, the player gets a fixed number of additional
rolls (usually just one). This way, a player might roll a 6 and another 6.
He gets 12.
There is a fault with this method of rolling dice: Some numbers may drop
out. In the preceding example, it's actually impossible to get 6, 12, 18,
24, and so on with an unmodified die roll. The counting goes ·4, 5, 7, 8·
It's possible to mechanically work around that, but I think the d10 provides
a more elegant solution. The d10 is numbered 0 to 9. If you count the 0 as 0
and 9 as the maximum value, your numerical progression will always be very
smooth. If a player made an open-ended d10 roll, he could possibly roll 9,
9, 9, and 0 to get 27.
- Counting Victories: The player rolls one or more dice.
Each die is evaluated separately to generate a number of victories. The more
victories the player gets, the better the outcome of the character's action.
For example, a player might roll 4d6 and evaluate the results against a
target number. Say the target is 2. If the player rolled 1,3,5,and 2, the
player would get 3 successes. If the target number had been 4, the player
would have only 1 success.
- Mass on Target: The player again rolls one or more dice.
This time, the results are tallied to produce a really big number. Well, the
player hopes it's a big number. The device is usually die roll vs. target.
For example, the player might roll 3d10. If the player rolled 3, 5, and 8,
his result would be 16. Of course, rolling dice this way greatly increases
the chance of getting a mid-range value.
- Many More Possibilities: I am the first to admit that
the examples and ideas I've presented here barely scratch the surface of
what you can do with dice, but I think these are the basic building blocks.
You can mix and match these methods to your heart's content.
- A Good Article: As it turns out, Shannon
Appelcline recently wrote a very
good article about the nature of random chance.
is deliberate determination of what happens based on
the capabilities of the character. If the character has the skill, if the
character has a resource such as hero points, or if the character has a
built-in capability that allows him to do certain things, the player can use
to resolve an event.
- Using skill to
resolve an event: Skill is usually based on character attributes or
skills. Frequently, a character with a low attribute or skill will only be
able to do simple, little things with that attribute or skill. A character
with a high attribute or skill will be able to do amazing things. If the
character's attribute or skill is too weak, the character will fail. If the
character's attribute or skill is sufficient, the character will succeed.
It's that simple.
For example, a character has a skill, Fencing 5,
where '0' is untrained and '10' is the best on the planet. The character
gets in a duel with an opponent who has Fencing 7. Using ability alone, the
character with Fencing 5 will lose every single time.
- Using a
resource to resolve an event: Resources are expendable units of success
that the player can spend during play. They are finite. Once used, they're
gone, though the player may have the opportunity to earn more. A resource
like Hero Points may temporarily improve character skill to ensure success.
The player spends the points to get the desired result. A resource like
Victory Cards may provide the character with instant victory. The player
plays a single card and gets the desired results. For more thoughts on this,
I refer you to Eric Brennan's wonderful article about Hero
- Using a built-in capability: Capabilities
often work with no muss or fuss because the rules say so. A character may
have the ability to cast certain spells or to do certain things without any
chance of failure. The player says the character is doing it and the
character does it thanks to Ability.
is resolution based on what a player wants to happen
in the game. The player makes a declaration. The declaration becomes a
mechanical device for resolving events.
For example, a group of
characters surrounded by enemies, running low on ammunition may make their
last stand. Before the end, a player declares, "·And the cavalry arrives in
the nick of time, distracting the enemy and giving us the chance we need to
escape." The GM allows this to happen because it's in the spirit of the
game. But nothing is free, so the GM replies, "The cavalry assault breaks
the enemy line, but they take very heavy casualties. It will be a long time
before they can help you again."
Using Chance, Ability, and Intent
methods of resolution are seldom used in isolation. A resolution mechanic is
rarely Chance, Ability, or Intent alone. The process for resolving events
almost always includes a combination of Chance, Ability, and Intent,
especially Chance and Ability.
Consider this common resolution mechanic:
- Player declares character
- Chance and Ability: Player generates a die result using
Attribute + Skill + Die Roll vs. Target Number. The player must
roll over the TN for the character to succeed.
Here, Intent is a qualifier. If the GM determines the player wants the
character to do something easy, the TN will be low. If the GM determines the
player wants the character to do something really difficult, the TN will be
much higher. Then, the die result is a combination of Chance and Ability.
The character's attribute and skill are both Ability. Small numbers mean the
character has little ability. Large numbers mean the character has lots of
Ability. Naturally, the die roll is Chance. I have a lot more to say about
all this, but that will fill the next installment. As always, thanks for