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Chapter 2: Skill mechanics and task resolution
2.1 Definitions
The following are some basic
definitions which may be helpful when navigating the task system - all
told, the task system is pretty straightforward, but to utilize it in its
whole, understanding these terms will make the "task" a little easier
Appropriate Traits:
A list of traits (usually 2) that are to be used when determining the BCS
for a given task.
Automatic Failure Level
(AFL): Percentile number at or above which failure is automatic, regardless
of the character's trait levels.
Base Chance of Success
(BCS): Usually derived from the sum of the 2 Appropriate Traits.
BCS is multiplied by the Ease Factor of a task to determine
the roll needed to succeed.
Ease Factor(EF): Factor
that determines the ease of success for a simple task. Ease factor is multiplied
by base chance of success (BCS) to determine the basic percentile number
(or less) needed to succeed in a simple task. The higher the Ease Factor
of a task, the easier it is to perform in general.
Ease Modifiers (EM):
Bonuses or penalties applied to the Ease Factor (EF) of a task due
to the situation at hand.
Goal: Part of the
Task Profile, the Goal describes the basic objective that
will be achieved if the character succeeds in the task.
Modified Chance of Success
(MCS): The number or less that a player must roll on d% to succeed
at a task. This number is usually found by multiplying the Basic Chance
of Success (BCS) by the Ease Factor (EF).
Simple Task: A task
in which it is only important to determine whether the attempted action
succeeds or fails; determining how well the character succeeds or fails
is not important.
Success-based task:
Task in which the margin by which the character succeeds or fails is important
in determining the actual outcome of the task.
Success level, or Level
of Success (LOS): Determined when performing a success-based task,
LOS describes how well the character succeeded is the task beyond
achieving the minimum goal of the task.
Task: A challenge
presented to the character during the game. The chance of resolving a task
is based on the characters' skills and attributes; success or failure at
the task is determined by a dice roll.
Task Profile: A format
that tasks are written in that gathers all the needed information about
the task in one location for easy reference.
Trait: Term encompassing
the Attributes and Skills of the character. Traits are used in determining
the chance of success at a skill.
2.2 Simple Tasks
A "simple" task does not
refer to how easy the task is to perform for the character. A simple task
is merely the basic type of task in Starfarer, in which it is only determined
whether the character succeeded or failed; it is not important to determine
how well the character succeeded or failed.
Tasks are written in a uniform
format that gathers all the needed information in one place. An example
of a simple task might be as follows:
You will notice that this
seems fairly straightforward, but we'll break it down for you for future
reference:
The first box is called the
"header", it contains only the goal of the task.
"To notice that the briefcase
has been switched" - this , the "Header" of the task, is called the goal.
The goal describes, in simple terms, what the task will accomplish if successful
in combat.
The second box is the "Probability
box".
"(Perception, Surveillance),"
- These are the Appropriate traits. Usually there will be 2 traits
listed here; simply add up the values of the appropriate traits to determine
the character's BCS for this task.
"x3" - This is the Ease
Factor term. Multiply this number by the BCS to find the character's
chance to succeed at this task (also called MCS), expressed as a
percentile.
Any other boxes (in this
case, only 1) are "Information boxes." Information boxes give information
on modifying and interpreting the task. In this case, the phrase "GM: Hidden
roll" lets the GM know that he should roll the result without informing
the players of the reason the roll is being made. If the roll is successful,
the GM will tell the character(s) what they noticed.
This "profile" may seem very
formal, and somewhat unnecessary, and to a certain extent it is. For the
most part, tasks are easy enough for a competent GM to make up on the fly.
However, some success based tasks have many possible modifiers and potential
results, and the profile helps keep everything straight (such as in the
case of combat tasks, as will be seen). Utilizing task profiles allows
the GM to introduce a higher level of detail into the action of the game,
if needed.
2.2.1 Simple Task Resolution
To determine whether a character
is successful at a task, multiply the BCS by the Ease Factor (EF) to find
the modified chance of success (MCS). Then roll percentile dice. If the
roll is LESS THAN OR EQUAL TO the MCS, then the task is successful. If
the percentile roll is GREATER THAN the MCS, then the character has failed
at the task.
Example: Jacob Thunder
is attempting the above task. It just so happens that Jacob is a recon
specialist, and has a Perception attribute of 6, and has a surveillance
skill of 3. His BCS for this task is (6 + 3), or 9, and so he has a modified
chance of (9 x 3) or 27% to notice that a particular pair of briefcases
have been switched. The DM rolls the dice for Jacob (normally, Jacob's
player would roll the dice for him, but in this case, the roll is hidden,
so the DM rolls) and come up 44, so Jacob is oblivious to the fact that
the 2 briefcases of concern have been switched.
2.2.2 The Success Table
On each character is a Success
Table. Basically, it is a multiplication table with some game terminology
notes in the periphery. This table is placed conveniently to help speed
play during the game, and is duplicated in Table 2.1.
The number shown in the table
is the Modified Chance of Success (MCS), the number that must be
rolled for the task to succeed.
2.2.3 Automatic failure
You will note that a combination
of high ease factors and high applicable traits will produce a very high
chance of succeeding - according to the success table over 100%. However,
regardless of how high one's traits are, the GM should impose a small chance
of failure.
By the automatic failure
rule, the Automatic Failure Level of any task is equal to 90 plus
the EF of the task - treating all EFs of less than 1 as 0 (Note than you
should never have to impose the Automatic Failure Level for Tasks
with an EF of less than zero, but under the more advanced success based
tasks, this does serve a function.) This gives a number between 90 and
100. If the percentile roll for success is greater than the AFL for the
task, the task automatically fails, regardless of what MCS is indicated.
2.2.4 Selecting Ease Factors
Note that the ease factor
5 column of the success table is bold. This represents a task of moderate
difficulty that a competent, talented professional (total BCS 10) has around
a 50% chance to succeed at. Similarly, relatively easy tasks, such a an
EF x10, would automatically succeed for the same person.
Conversely, an EF 1 or ½
task is extremely challenging, even for a very talented individual. Levels
2 through 4 represent medians, that are very challenging for a modest character,
but less so for a highly skilled character.
The GM may select the level
of difficulty of a variety of such tasks on the fly with a relative amount
of ease. The GM may also designate some standard tasks and assign modifiers
for adverse (or favorable) conditions as he sees fit. For example, the
GM may have decided ahead of time, that piloting a gunboat through a narrow
trench safely would have an EF of 5. But if the players, being the unpredictable
entities that they are, decide to try piloting their starship down the
trench instead, this would incur a negative ease modifier as piloting a
massive starhip in confined quarters is significantly more difficult than
piloting a lowly gunboat. If the GM imposes a -2 EM to the task, the effective
EF of the task would be 3. But maneuvering a small, agile hoverbike down
the trench may be a cinch - the DM might grant a +2 for such an attempt,
giving an effective EF of 7 for the task.
To notice that the briefcases
have been switched:
(Perception, Surveillance),
x3
GM: Hidden roll.
Table 2.1 Success Table:
|
BCS: |
|
||||||||||
| ½ | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | |
| 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 |
1
2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 10 11 11 12 12 13 13 14 14 15 15 |
2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 |
4
6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 |
6
9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60 63 66 69 72 75 78 81 84 87 90 |
8
12 16 20 24 28 32 36 40 44 48 52 56 60 64 68 72 76 80 84 88 92 96 100 104 108 112 116 120 |
10
15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 |
12
18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120 126 132 138 144 150 156 162 168 174 180 |
14
21 28 35 42 49 56 63 70 77 84 91 98 105 112 119 126 133 140 147 154 161 168 175 182 189 196 203 210 |
16
24 32 40 48 56 64 72 80 88 96 104 112 120 128 136 144 152 160 168 176 184 192 200 208 216 224 232 240 |
18
27 36 45 54 63 72 81 90 99 108 117 126 135 144 153 162 171 180 189 198 207 216 225 234 243 252 261 270 |
20
30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 300 |
2.2.5 High ease factors and automatic tasks
The GM may wish to assign
ease factors greater than 10 for routine tasks, in which case, the only
role that difference in traits play will usually be time it takes to complete
the task. Usually, it is best assumed that for any task with a EF greater
than 10, completion of the task is automatic provided that the character
has the appropriate skills to complete the task.
2.2.6 Low ease factors (Optional)
Modifiers to ease factors
are usually expressed as a positive or negative number (e.g., +1, -2).
Any modifier that takes the EF to less than one should be treated as modifying
the EF to ½.
The GM may find it desirable
to use very low ease factors. For this purpose, each successive EF below
½ is obtained by subtracting 1 from the value of MCS given on the
success table for 1/2. Thus if a character with a task BCS of 10 was attempting
an EF 1 task with a -2 ease modifier, the total EF is -1. The character
would need would to roll a 4 or less on d% to suceed (for EF that is modified
to "0", the character would need ½ of thier BCS, for and MCS is
5. For the modified EF of -1, the required roll is the same as the EF ½,
or 5, minus one, for a total of 4 .) For the purposes of label, EF ½
would be equivalent to "EF 0", and each smaller EF is labeled by its negative
magnitude, i.e. "EF -1", "EF -2", etc.
2.3 Success-based Tasks
Sometimes, whether you succeeded
or failed at an attempted task is not the only relevant outcome of the
task - sometimes it is important to know more. As an example, just knowing
that you hit your enemy will not be enough information to know exactly
what happend. You must also know HOW WELL you hit the enemy.
This is accomplished through
the use of Success-based Tasks. The basic concept is that by examining
the dice roll compared to the character's BCS, you can determine the resulting
Success level (also called Level of Success, or LOS.)
2.3.1 Basic concepts
When determining a Success-based
Task, you will have to find your characters BCS for that task and roll
percentile dice. But unlike simple tasks, you are not shooting for just
one number that you must roll equal to or less than. Generally speaking,
the lower you roll, the better.
When resolving a Success-based
Task, you must determine the Modified Chance of Success as you
do for a simple task (i.e., by multiplying Ease Factor by BCS.)
Just as in simple tasks, modifiers may be applied to the Ease Factor
and BCS.
If roll greater than the
Modified Chance of Success, then you have failed at the task. If
you roll less than or equal to the Modified Chance of Success, you
have succeeded at the task and must find the Level of Success.
2.3.2 Generating Levels of Success (LOS)
To generate a Level of
Success, determine the BCS of the task as for simple tasks. Then roll
percentile dice. Consult the row corresponding to the task BCS on the success
table, and count the number of results that are both less than the MCS
and greater than or equal to the percentile roll. The number of
such results is the Level of Success. You can also do this simply
by putting your finger on the MCS on the row corresponding to the
BCS. Then, moving right, count one for each colum, stopping at the
first number less than the number rolled on d%.
If you succeeded in the task
but failed to roll low enough that your roll is less than any numbers in
the columns to the left of the MCS, then you still succeeded, but
your LOS is zero. This is called a marginal success. Such
a result means that you succeeded in the task, but did not do anything
beyond the basic goal of the task.
Example: Kitai Kurugumi,
an intelligence agent for the Orchid Gunner mercenary unit, is firing a
laser pistol at an opponent. He has a skill of 5 with the laser pistol,
and a dexterity of 7, giving him a BCS of 12 for the task. The task has
an Ease Factor of 5 at this range with a laser pistol, but the GM
imposes a Ease Factor modifier of -1 due to darkness, thus the modifed
EF for this task is 4. This makes the MCS of this task 48 (4 x 12
= 48) Kurugumi's player rolls d% and comes up with a 23. He cross-references
table on the row on which the BCS is 12. Two numbers (36 and 24)
on that row of the table are less than the MCS (48) and greater
than or equal to the dice roll (23). Thus, the resultant LOS is
two.
2.3.3 Interpreting LOS
The GM should feel free to
interpret the meaning of various LOSs. However, if a frequently used task
is being developed for use in the game, the LOSs should be listed in an
information box with the task writeup.
Note that results with a
Level of Success of 0 is also termed "marginal successes", and usually
represent the minimum result that fit the description of the desired goal.
For example, in the combat system, a LOS 0 hit is called a "marginal hit"
and results in a minimal amount of damage.
2.3.3 Negative Success Levels.
Though the usual use of Success-based
Tasks is to determine how well a character succeeded, the GM may also
use the negative LOS number to determine how bad the character failed!
However, unless the task is particularly hazardous, negative effects should
be resigned to larger negative numbers - usually, it should take a LOS
of -2 to -5 for any significant negative effect (other than failing to
achieve the desired goal) to take effect.
To find negative Levels
of Success, count each result on the row corresponding to the BCS that
is greater than the MCS and less than or equal to the percentile
roll.
2.3.4 Extremely high LOSs (optional)
Occasionally a player will
roll a nice, low number - like 01 - that the GM may rule as being a truly
exceptional success. One way to handle this is that if the d% roll for
the task is less than ½ of the BCS (which is the leftmost column
on the table), then the character gets the LOS equal to that they would
have received if they rolled exactly ½ the BCS, plus an additional
+1 LOS for each point the roll is less than ½ the BCS.
Example: Lance Detwiller
is piloting his speeder bike to avoid enemy fire. The appropriate attributes
for this task are his Dex, which is 6 and Pilot: Atmospheric, which is
4. This gives him a BCS of 10. The EF of the task is 5. Lance's
player rolls the dice for the task and rolls an 02! For a BCS of 10, this
is less than the 5 he would need to succeed at an EF ½ task. Rolling
a 5 would give Lance a LOS of 4 on this task, plus the roll of 2 is 3 less
than the 5 needed for a +4 LOS, so his total LOS is +7 (the basic +4, plus
1 more for each 1% rolled under the ½ BCS threshold).
2.3.5 Automatic failures and Low LOSs
Automatic Failure Level
is used for Success-based Tasks in the same way as for simple tasks (see
section 2.2.3.) However, if the GM is keeping track of failure levels for
the task, the following rules apply.
The LOS of a task
for which the dice roll is equal to or greater than the AFL is equal
to the normally determined LOS of the task minus one for each point the
roll is over the AFL, with a maximum value of -1.
Example: Two scientists
are researching the ruins of an ancient civilization and are tryig to determine
the cause of their demise. The appropriate traits are Reason and Archeology.
The first scientist has 9 res and 9 skill, for a BCS of 18. The second
has 6 res and 6 skill for a total of 12 BCS. The task has an EF of 7,
and thus a AFL of 97.
Scientist 1 rolls d% and
gets a 97. The MCS for this task is 126. Ignoring the automatic failure
rule, this would normally give him a LOS of 1, which would normally
be considered successful. However, the roll was at or above the Automatic
Failure Level, the LOS is lowered to -1, which is considered
a failure, but just barely. Scientist 1 is baffled, but nothing bad comes
about because of it.
Scientist 2 also rolls d%
and rolls a 99! His MCS for this task is 84. This would normally give him
a LOS of -2, which is bad enough, but he also subtracts an additional
2 because he rolled 2 more percentage points over the AFL. His final
LOS is -4! Not only does he not have a clue concerning what caused
the demise of the civilization, he comes to a conclusion that is totally
wrong!
2.3.6 Mechanical Failures
You may want to define some
failures that are strictly independant of trait levels, such as mechanical
failures. In this case, do not use the determined negative LOS level to
decide what undesirable effect is inflicted on the character or equipment;
instead, if a percentile roll is made that is greter than the pre-defined
failure level, ignore the LOS and impose a mechanical failure.
The percentage roll needed
to impose a mechanical failure should be at least equal to the AFL. Typically,
most modern mechanical devices fail rarely, and it is appropriate to only
institute a mechanical failure on a d% roll of "00", or perhaps on a lower
number if the equipment is old, poorly designed, or poorly maintained.
As a guideline, add an additional percentage point to the spread required
for mechanical failure for each of these factors.
Example: Operating
equipment on a new, well maintained, well designed ship would only result
in a mechanical failure on a "00" (if at that!). If the ship was old, missed
a scheduled overhaul, and was a hunk of junk to begin with, any operational
task resulting in a d% roll of 97 or more might result in mechanical failure.