One Rule to Rule Them All

Every character has a PCS (primary chance of success) and BEF (base ease factor) for each attribute and skill he/she possesses.

BEFs often are formulae involving E and G. These are references to Environment and Gravity familiarities. Substitute in the character's corresponding familiarity. (You may occasionally encounter references to T, for temperature familiarity, which has been removed from the game system. If you see it, remove it or substitute 2, whichever makes more sense.)

Modifiers. A given task may receive modifiers for difficulty. These modifiers are added together to form a single modifier for the task as a whole and then applied to the BEF to yield the final EF (ease factor) for the task.

Applying modifiers to Ease Factors is just like adding normally, except that Ease Factors go: 0, 0.25, 0.5, 1, 2, .. , 14, 15. Ease factors cannot be modified below zero or above fifteen.

Success Change. To determine the SC (success chance) (expressed as a percentage) for any task, multiply the PCS by the EF. The Success Chance may turn out to exceed 100.

To determine whether an action succeeds or fails, you roll D100 and compare the result to the SC.

Finally, the degree of success or failure is called a QR (quality rating).

Quality Rating Table

D100 Roll



>SC, and ends in "0"


Fumble. The task actually ran opposite to intention.

>SC, or "100" < SC


Failure. The task did not achieve anything positive.

<= SC, or "99" < SC


Bare/Mediocre Success. The task took longer than expected and/or achieved less than might have been hoped.

<= SC/2


Competent Success. The task was a solid success, but nothing special.

<= SC/5


Good. The task took less time than expected or achieved better results.

<= SC/10


Brilliant. The task took far less time than expected or achieved far better than expected results.

A roll of 99 may never result in better than QR4
A roll of 100 may never result in better than QR7

Optional Rule: QR5 & QR6

This rule allows explicitly for Bare Success and Bare Failure. Personally, I feel free to treat an QR4 as a bare success if it's dramatically appropriate and any QR7 as a bare failure likewise.

The rule is simply this: a roll which would otherwise be a QR4 that ends in "5" is a QR5. A roll which would otherwise be a QR7 that ends in "6" is a QR6.

Optional Quality Rating Table

D100 Roll



>SC, ends in "6"


Bare Failure. The task failed, but teeters on the brink of success.

<= SC, ends in "5"


Bare Success. The task succeeded, but is hanging on by its fingernails.


Rule of Thumb Modifiers

Task Difficulty


Trivially Easy


Very Easy


Relatively Easy




Relatively Hard


Very Hard


Extremely Hard


Near Impossible


This table is really all you need to remember. The many other modifiers listed in these rules are really just examples of how this can be applied in the light of all the different factors that bear on the difficulty of a given task.

It also follows that a task can be rendered easier or more difficult by several different factors, and that these effects are cumulative.

E.g. being wounded incurs a negative modifier to all activity, while shooting at a small target is also hard, as is firing at a distant target, as is firing at a dodging target, as is using a badly designed weapon. All these modifiers have a cumulative effect, that might go well beyond the -7 listed for "near impossible" in this table. So it is and so it should be.

Similarly, positive modifiers can accumulate so as to make a task almost impossible to fail. Performing a task with excellent equipment, in familiar and conducive surroundings, aided by an excellent tutor, and armed with profound knowledge of the particulars may take a task well beyond "trivially easy".

Of course, modifiers cannot take the final ease factor of a task below zero or above fifteen, so there are always limits.

Opposed Resolution

There are two kinds of opposed resolution in ForeSight.

Who Got The Best Result? Both characters roll against their appropriate attribute/skill. The better QR wins. If there's a tie: reply hazy, try again later. Big difference in results equals easy win. Small difference equals narrow win. Several ties before result equates to drawn-out struggle.

This works well for cases where both people are doing the same thing in opposition: e.g. a tug of war, arm wrestle, chess game, or tennis match; and almost as well for cases where one is attempting to counter the other's actions: e.g. one person is trying to keep hidden via stealth while the other is attempting to find him/her by search.

This case is generally used for simple contests, stealth vs. PC, stealth vs. Search, and melee combat parries and dodges.

[Un]Do What I Do. This is the reason for the numbers in QRs. Simply treat the QR number as the BEF of the opposed task, or subtract it from 6 and treat it as the BEF of a follow-up task.

This, more complex case, works well for answering questions such as "how hard is it to counter the work of someone else?" or "how easy is it to do the next step?": e.g. if you're trying to hack into a computer system, how good is the security? if you're building a device, how good was the design?

This case is generally used for complex resolutions, particularly mult-stage tasks such as plan, design, and execute, and cooperative tasks.


It may not be obvious so far, but Fields of Knowledge are a crucial part of the resolution system, especially in technologically-centred settings (which may include magical settings).

One of ForeSight's key assumptions is that capabilities are roughly divided into skills (think of attributes as basic sorts of skills) and knowledge, and that the former are gradually honed while the latter is acquired and built. One either has or hasn't got a piece of knowledge; one can either remember a fact or not. This is obviously an over-simplification, but it works, and has been endorsed more often than condemned.

As far as resolution goes, knowledge works like this: if a given task entails the possession of relevant knowledge, then the degree to which that knowledge is possessed by the character affects the difficulty of the task (in the shape of an ease factor modifier).

Knowledge Modifiers

The character's knowledge pertaining to the task is...



-5 or worse

Barely sufficient

-4 or -3


-2 or -1






+2 or +3

Note that the GM can allow a given task to be performed with different sets of knowledge (and skills for that matter) if he/she deems appropriate. E.g. one character might try to disarm a security system using the Security Systems field and the Diagnose and Repair skills. Another might use Physics and Theory. Another might use Electrical Engineering and IN. They would probably use different approaches, and would probably incur modifiers. A character with all these fields of knowledge might gain the "profound" modifier.

Knowledge has its limits

Many tasks require no real knowledge, and for them these rules are completely irrelevant. E.g. a character with profound knowledge of the geology of a chasm will be no more adept at jumping across it for this knowledge, and markedly less so than an athletic ignoramus.

When at first you don't succeed...

One of the classic tactics players will adopt in role-playing games is to keep trying something until they get a good die roll. It is up to you to recreate the real world frustrations that prevent this tactic from being universally applied to all the world's problems, rather than to blithely refuse to allow second attempts (as most D&D dungeon masters do when thieves try to repick locks).

Time. Tasks at the very least take time, and in many cases time will be in short supply. In general, it may take longer to attempt a previously failed task again because a new approach will probably be needed (a bare failure is another question entirely).

Other Costs of Failure. Tasks may involve the expenditure of consumables (e.g. lockpicks may get broken or bent out of shape; phone phreaks may run out of washers), fatigue, or money.

Secondary Risks. Failure brings with it the possibility of detection, or the environment may be one which is intrinsically unsafe, like an underground complex full of patrolling guards.

Did the task fail or was it impossible to begin with? Especially in the case of complex tasks, the GM should distinguish between the concept of the task being performed incorrectly (actual failure) and the characters discovering that the task is simply impossibe (at this time or given current knowledge). A simple way to do this is to privately roll to determine the impossibility of the task, and resolve only the quality of the attempt. The players could then achieve a QR1 but be told that all they've discovered is that their approach, even when executed flawlessly, doesn't work.

Is this good role-play? Real people get frustrated, run out of ideas, and give up. You may wish to require characters to make a WP roll to keep at something, or simply start questioning whether the player really thinks that his/her character would bang his/her head against that particular wall for so long and let the player decide what to do.