
YATTS: Yet another T4 task system. 
----------------------------------- Version 1.5 ----

by Paolo Marino (marino/AT/inrete.it)


Overview
--------
What follows is an attempt to modify the Task System published in the
first edition T4 book in order to solve some of its problems.

The original system has some strong points, which I'd like to
preserve:

- It's fast and easy
- Uses six sided dices only
- Allows for easy conversion of older edition adventures and 
  characters

Unfortunately the published system suffers from some serious
drawbacks. First and foremost, the current task rules give
ludicrously high chances of success for tasks labeled "Staggering" or
"Impossible". Other (minor) problems are the cumbersome use of half
dices for some of the task levels, and the fact that character stats
influence the results much more than skill levels.

YATTS aims to provide a fast and easy system which can be used as a
replacement of the current T4 system. Ideally you will be able to
take any adventure published for T4 and run it with YATTS without
modifications.

Other Traveller fans have tried to correct these problems with
various house rules. Usually they increase the number of D6 required
for the more difficult tasks. My solution is different. Only 2d6 are
needed, just like in CT, and the task system is a simplified version
of the one in T2300. In fact, I adapted and modified the system
described in Traveller 2300, trying to tailor it to CT/T4
characteristics and skill levels.

Even if the complete text for YATTS may be of medium length, don't
feel intimidated. I've included examples, commentaries and tried to
cover common situations and requirements. The actual system is easy,
and uses just one Task Difficulty table like the original T4 system.

In Appendix B I've added an optional system for experience rolls,
aimed at correcting another problem in the T4 rules.


Acknowledgments and Credits
---------------------------
Traveller is a registered trademark of Far Future Enterprises. 

Thanks to all the people in Traveller Mailing List for ideas,
comments and inspiration, with a special thanks to William F.
Hostman <aramis@asylumbbs.com> for his comments and ideas for YATTS.

The YATTS playtesters: 
 Pietro Andreoletti 
 Alberto Casciani
 Marco Mesturino 


---------------------------- YATTS Rules start here ------------

Task Resolution
---------------
The basic mechanisms for determining success in a task is the following:

Compute _Stat Bonus_: divide relevant characteristic by 2, rounding
up (For example INT of 7 gives 7/2=4).  
Add relevant _Skill(s) Level(s)_.

Roll 2d6 and add the result to skill and stat bonuses. 
The total must be equal or greater than the task target number,
which is determined as follows:

Task                Target   
Difficulty       |  Number
----------------------------
Easy             | Auto/(8)
Average          |   11
Difficult        |   14
Formidable       |   17
Staggering       |   20
Impossible       |   23

If you prefer higher chances of success, you may consider decreasing
all the Target Numbers by 1. Refer to the tables in Appendix A to
evaluate the effects of the proposed task scale.

Modifiers
---------
Any DM applied to a T4 roll (for example the -5 for double damage in
combat) can be applied to YATTS without change.


Unskilled and Lev-0 Tasks
-------------------------
The original T4 systems differentiates between tasks which can be
attempted by unskilled characters (tasks involving Default Skills,
such as Brawling and Perception) and tasks which cannot be attempted
without at least level-1 in a given skill (like Engineering, for
example).  Unfortunately some other situations, like familiarity with
a skill or substitute use of skills have not been adequately
explained.

In YATTS, for any given skill, a Character may have:

1+ level(s) The character has some experience in the field,
            adds his skill(s) level(s) for determining success, 
            and suffers no penalties when assessing Task Result.
            As for T4 rules, the character automatically
            succeeds at Easy tasks. No roll is required. 
0-Level     In this case the character uses only the relevant
            stat bonus for determining the base chance.
	    Easy tasks require a roll: Target Number is 8.
Unskilled   No knowledge of the relevant skill. Characters
            can only attempt tasks requiring default skills 
            (like in T4), use the relevant stat bonus only 
            and, on top of this, they suffer a -3 penalty to 
            the roll result. This is equivalent to raising
            the task difficulty by one level (easy becomes 
            average, and so on. Impossible Tasks require 26+ 
            to succeed). See also the JOT section.

_Level-0 vs. Unskilled_
Level-0 describes characters which have some degree of familiarity
with the task. This concept was introduced in The Traveller Book, and
something remotely similar still lingers on in T4. For an example of
this, people with Pilot-1 will have an automatic Ship's Boat-0
familiarity according to the T4 manual.
Another use for Level-0 skill occurs when the character is using a
cascade skill at a penalty, as a replacement for another skill in the
cascade: for example someone which has Pistol-1 can use a Rifle at
Rifle-0, (see page 37 of the manual).


Task Resolution Table
---------------------
Here is a table which summarizes the difficulty levels and
incorporates the penalty for unskilled characters.


------------------ Task Resolution Table ----------------

                  Target Number
               Skilled	|	  
 Task Level    (Lev 0+) | Unskilled
-------------  ---------|------------
   Easy [1]    Auto/(8) |    11
   Average        11    |    14
   Difficult      14    |    17
   Formidable     17    |    20
   Staggering     20    |    23
   Impossible     23    |    26
   
[1] The Target number of 8 is required only for Skill-0
    characters attempting Easy Tasks. Skilled characters
    with level-1 or more don't roll for easy tasks.
---------------------------------------------------------
	       

Special Results
---------------
Natural rolls of 2 or 12 are considered special results.
A roll of 2 is a negative special. You add 5 to the target number and
reroll.
A roll of 12 is a positive special. You subtract 5 from the target
number and reroll.
Note that this can theoretically go on and on, with target numbers
being shifted upward and/or downward until a player stops getting 2
or 12.


Critical Success
----------------
If the final result of roll+stat+skill bonuses is equal or higher
than the target number, the task succeeds. If the player's result is
at least 6 points higher than the target number, the success is a
critical success, and the referee must decide special effects for the
situation (for example, in case of combat, the hit could cause double
damage or ignore target armor, player's choice).


Critical Failure
----------------
If the final result of roll+stat and skill bonuses is lower than the
target number, the task fails. If the target number is at least 6
points higher than the player's result, the failure is a critical
failure, and the referee must decide special adverse effects for the
situation (bullet hits the wrong target, runner trips and falls over,
vehicle suffers a mishap, and so on).


Notes About Critical Failures
-----------------------------
Here are some notes regarding interpretation of criticals in YATTS.

_Firearms_
Don't overuse the "Weapon Jams/Misfires" interpretation for critical
failures during combat. In YATTS critical failures are relatively
common and usually depends more on skill/task ratio than on pure
chance. For example a low skill character firing at long ranges will
have high chances of critical failures, much higher than TL6+ gun
jams probabilities. Use your judgment in evaluating failures,
especially in combat. A critical failure at very short range could
mean that the attack still hits, but does minimum damage for the
weapon type (3 for a revolver, for example).

_Recovering from Critical Failures_
Optionally, if the task allows for backtracking and error recovering
(for example writing a computer program or performing non destructive
lab tests) the referee may allow the player to reroll adding a -3
penalty to the next roll (i.e. task difficulty is increased by one
step). If time, money or other resources are critical, double the
amount required for the task.


Multiple Actions in Combat
--------------------------
T4 allows for multiple attacks against different targets in melee
combat.
In YATTS, each attack beyond the first one gets a cumulative -3
penalty (equivalent to a one level increase in difficulty).  So if
punching an enemy (for a skilled character) is an Average
DEX+Brawling task, hitting more foes will become an Average task for
the first, a Difficult task for the second one, a Formidable for the
third and so on. Failing one of the tasks will not affect the
following one(s):  you could miss the first, hit the second and miss
the third one, for example. Referee may overrule this in case of
critical failure.
 

Cooperative Tasks
-----------------
For certain tasks, more than a character can participate. In these
cases, one of the participants will assume leadership, and all others
will contribute their skills or stats, depending on the type of task.
Apply a -1 penalty for each participants.  The penalty represents the
increasing difficulty in coordinating the efforts of a group of
people.
If the task requires skills, the other participants will only add
their relevant skill levels, and not the stat bonus.

Example 1: Porting of a program to a different computer system.  INT,
Computer, Difficult.
Yoran Juuush, INT 9, Computer 3 is leader.
Gohan Huran (Computer 2) is a programmer.
Rold Lena (Computer 3) is another programmer.
Their collective throw is 5(INT 9/2)+3(Juush skill)+2(Huran
skill)+3(Lena skill) -3 (number of people cooperating) for a final
result of 10+2D6.
Example 2: Pushing a wheeled vehicle off the road.  The referee
decide that this requires a combined strength of 25+ to succeed.
Theo Saar (STR A), Krees Werr (STR 7) and Kina Orru (STR 9) start
pushing. Their collective strength is 10+7+9-3=23. They will have to
ask someone else for help, or find another solution.


Quick contests
--------------
In some cases two or more characters will need to directly confront
their respective stats (the canonical example being armwrestling
contests using the STR stat). This is best resolved by having all
participants roll 1D6 and adding it to the relevant stat.  Higher
total wins. Reroll any ties if the situation requires a clear winner.
Other kind of contests (for example a game of poker) will require
skills, instead of raw stats. In these cases, apply the following
procedure:
  All the participants roll two dices and add the result to the skill
  level and the relevant stat bonus. Remember to use the -3 penalty for
  unskilled characters, and apply the +5/-5 plus reroll rule for
  specials (i.e.: for natural rolls of 2 and 12).

_Example_: 
   Three characters decide to spend some time playing a card game.
     Allol has Int B and no Gambling skill
     Bozepe has Int 7 and Gambling-1
     Churnal has Int 9 and Gambling-2

   Allol rolls 2d6. 7(roll)+6(Int/2)-3(no skill) gives 10
   Bozepe rolls 2d6. 8(roll)+4(Int/2)+1(skill) gives 13
   Churnal Rolls 2D6. She rolls a 2, negative special. 
     She then rerolls with a -5 penalty for the special.
     7(new roll)-5(penalty)+5(Int/2)+2(skill) gives 9

   Bozepe got the highest result, and therefore is the winner.


Uncertain results
-----------------
In some cases, the character can't be immediately certain of the task
result. Some example could be investigating a rumor, or searching
for clues, or checking a computer program for bugs.  For uncertain
rolls,  the referee and player should both roll the 2d6. The referee
roll should be secret.

Both fails: 
       Complete failure, in the example, some or no bugs were found,
       and the program is still buggy.
Both succeed: 
       Complete success. All the bugs are identified and no 
       further problems will manifest.
One roll fails and 
the other succeeds: 
       Partial success. Some of the bugs are found, but the
       program is not stable (and the player will not know what the
       referee roll was, so s/he will be uncertain of the true result.)


Predetermined Assets
--------------------
In certain cases the Task number is defined without using
characteristics or skill levels. Some of the equipment in the _Central
Supply Catalog_, for example, has a predefined asset, like the TL8
Translator, which uses a task number of 15 for determining successful
translation (which is considered an Average task).
In order to translate these in YATTS terms, use 2/3 (two thirds) of the
stated number: a TL8 translator has a base asset of 10 (15*2/3).
Always apply the 2/3 rule *after* any reduction in the base asset: the
TL8 Translator description for example, states that the asset becomes
11 when a sentence requires an Int of 4. So 15-4=11, 11*2/3 = 7.  The
base assets becomes 7 in Yatts.


Jack-O-T
--------
JOT gives a chance to attempt a task even when you lack the relevant
skill in it. Whenever the character wants to use JOT, he must roll a
Difficult JOT task using the same stat required by the task they are
trying to roll. 
If the roll succeeds, the character gains the temporary ability to roll
for the original task as if s/he had a level-0 in the relevant skill. If
the roll fails, the character can't try it anymore.

Example:
Toser attempts an Average _Sensor_ roll, even if he has no Sensor
skill (but he has JOT 2 and Int 9).
He first rolls a Difficult (14) JoT+Int task; he rolls
9+2(JOT)+5(Int/2)=16 and succeeds. Now he can try the _Sensor_ roll
using 5 for his Int and 0 for his Sensor skill.

N.B.: If the task requires more than a roll, you must do a separate
JoT roll for each. The 0-level "works" only for the subsequent roll, and
does not confer any special bonus even for similar tasks you encounter
later.


APPENDIX A: Chances of success
------------------------------

A small rundown of success chances will help you decide if the
system looks sound.

An average character (stats at 7) with professional level skill
(Skill level 3), will be column 7.

(Stat/2)+Skill |   2    3    4    5    6    7    8    9   10   11   12   13
---------------|------------------------------------------------------------
Task Difficulty|
Easy        (8)|  72%  83%  91%  97%   A    A    A    A    A    A    A    A   
Average     11 |  28%  42%  58%  72%  83%  92%  97%   A    A    A    A    A
Difficult   14 |   3%   9%  17%  28%  42%  58%  72%  83%  92%  97%   A    A
Formidable  17 |   I    I    I    3%   9%  17%  28%  42%  58%  72%  83%  92% 
Staggering  20 |   I    I    I    I    I    I    3%   9%  17%  28%  42%  58%
Impossible  23 |   I    I    I    I    I    I    I    I    I    3%   9%  17%

A:Automatic except for critical failures.
I:Impossible except for critical successes.


Here is the same table for unskilled characters. Note that having no
skill, the base number can't get higher than 8 (15/2).
The table applies the -3 penalty directly to the Task difficulty
number.

(Stat/2)       |   1    2    3    4    5    6    7    8   
---------------|----------------------------------------
Task Difficulty|  
Easy        11 |   17%  28%  42%  58%  72%  83%  91%  97%
Average     14 |    I    3%   9%  17%  28%  42%  58%  72%    
Difficult   17 |    I    I    I    I    3%   9%  17%  28% 
Formidable  20 |    I    I    I    I    I    I    I    3%   
Staggering  23 |    I    I    I    I    I    I    I    I
Impossible  26 |    I    I    I    I    I    I    I    I


A Stat-7 Skill-3 character has 17% chances of a critical success for
Average tasks. In order to acquire critical successes at higher task
difficulties he must obtain positive DM+, for example with a natural
roll of 12. This means less than a 1% chance.
On the other hand, he will not face critical failures for Tasks of
Difficult or lower level, unless he gets a roll of 2.  Starting at
Formidable his chances of critical failure are 9%, 42% at Staggering
Tasks and a whole 100% for Impossible tasks.


APPENDIX B: Experience
----------------------
The current system for Experience advancement in T4 has been heavily
criticized: it tends to give a rate of advancement which many
consider too fast, and yields inflated levels of skills (8+ being
relatively common).

The present system substitutes the original 1D6 roll test for skill
advancement with a task roll. The task difficulty increases with the
skill level. The stat used in the task is chosen by the player among
the ones used in the relevant skill description.  The "advancement"
roll is not based on any skill.

Here is the the advancement roll table
 
Skill Level | Difficulty  Target   Cost
 U->0          Easy         8       2              
 0->1          Easy         8       2
 1->2          Easy         8       1
 2->3          Average     11       1
 3->4          Difficult   14       1
 4->5          Formidable  17       1
 5->6          Staggering  20       1 
 6+>           Impossible  23       1

Testing a default skill from unskilled to level 0 and from Level-0 to
Level-1 costs 2 points.
Testing a skill costs 1 Exp.Point for skills which the character
already knows at level-0 or better.
Skill Points may be used as positive DM. They may be spent after the
roll. Experience Points can't be carried over between adventures.
Rules for special rolls (2,12) apply. Criticals don't have special
effects.

_Example_:
Kather Sha'al (Upp: 797A97) has gained 3 Exp.Points in her latest
adventure.
She has Brawling 2, and tries to gain Brawling 3.
Brawling uses either STR or DEX. She obviously decides to use DEX for
the test and pays one Exp.Point for testing her skill.
Her Stat bonus is 9/2=5.  
She rolls and gets a 5. Paying another Exp.Point she raises it to a
6, 5+6=11, the task is a success and she now has Brawling-3.

APPENDIX C: Assorted Rulings and Modifications
----------------------------------------------
Here ares some others things I've decided to modify for various
reasons. They are not part of YATTS, strictly speaking, but they
address some minor problems I've experienced with the current T4
rulings.

Cascade Skills
--------------
The current rulings for cascade skills makes you potentially "waste"
levels. For example, a character with Pistol-3 and Rifle-1 will have
very little reason to use (and so raise) the Rifle skill, given
that his Pistol ratings gives him a better chance to hit.
When using a cascade skill as a replacement of another related skill,
the level for the substituted skill will be no more than 1.
Pistol-1 gives you Rifle-0, Shotgun-0, SMG-0.
Pistol-2+ gives you Rifle-1, Shotgun-1 and SMG-1, and no more,
however high will the Pistol skill go.
