Editing GURPS (section)

==Overview of the GURPS mechanics==
===Character points===
A character in GURPS is built with character points. For a beginning character in an average power game, the 4th edition suggests 100&ndash;150 points to modify attribute stats, select advantages and disadvantages, and purchase levels in skills. Normal NPCs are built on 25 or fewer points. Full-fledged heroes usually have 200&ndash;250 points, while superheroes are commonly built with 400&ndash;800 points. Using character points, Gamemasters can easily balance the power of foes to the abilities of the player characters.

===Attributes===
Characters in GURPS have four stats: 

*'''Strength (ST)''' A measure of the character's raw muscle power.
*'''Dexterity (DX)''' A measure of the character's physical coordination.
*'''Intelligence (IQ)''' A measure of the character's mental capacity.
*'''Health (HT)''' A measure of the character's bodily stamina. 

Having only four stats is arguably much simpler compared to other role-playing games which can have several main stats that cover more defined abilities. Each stat has a number rating assigned to it. Normally they begin at 10, representing typical human ability, but can go as low as 1 for nearly useless, to 20 (or higher) for superhuman power. Anything in the 8 to 12 range is considered to be in the "normal" area for humans. Basic Stat Levels of 1&ndash;4 are considered to be so far below the human norm that they are only usually used for severely handicapped characters. Skills over 14 are said to make you famous for that ability, and skills of 18 and above make the character among the greatest human beings who ever lived in that field.

Players assign these ratings with points. The higher the rating the more points it will cost the player, however, assigning a stat below the typical 10 gives the player points back to assign elsewhere. Since Skills are almost all based on Dexterity or IQ, those attributes are twice as expensive (or yield twice the points, if purchased below 10). Stat ratings also calculate several derived stats for the character, called Secondary Characteristics, such as Basic Speed, Move, Willpower, Perception, Hit Points, Fatigue Points, Basic Lift, Basic Damage, and others.

===Advantages and Disadvantages===
A player can select numerous Advantages and Disadvantages (including above-average or below-average Wealth, Status and Reputation) to spice up the character with special abilities and weaknesses. These are categorized as physical, mental or social, and as exotic, supernatural, or mundane. Advantages benefit the character and cost points to purchase. Selecting Disadvantages returns character points. Disadvantages include such positive attributes as honesty and truthfulness which limit the way a character is played. There are also many Perks and Quirks to choose from which give a character some personality. Perks (minor Advantages) and Quirks (minor Disadvantages) benefit or hinder the character a bit, but they mostly add role-playing flavor.

Enhancements and limitations can tailor an advantage or disadvantage to suit. These modify the effects and point cost of advantages and disadvantages. For example, to create a "dragon's breath" attack, a player would select the burning attack 4D advantage (normally 20 points) and modify it as follows: cone, 5 yards (+100%); limited use, 3/day (-20%); reduced range, x1/5 (-20%). The final percentage modifier would be +60%, making the final cost 32 points. This addition to the system greatly increases its flexibility while decreasing the number of specific advantages and disadvantages that must be listed.

===Skills===
Complementing the stats are numerous skills. A player buys skills with character points. Skills represent physical and mental areas of specialty which can prove useful in the game. Skills vary widely, from Acrobatics to Vehicle Piloting. The availability of skills depends on the particular genre the GURPS game is played. For instance, in a Medieval Fantasy world, skills for operating a computer, or flying a fighter jet would not normally be available for the player to choose unless they time traveled. Skills are rated by level, and the more levels purchased with character points, the better the character is at that particular skill. 

Skills are categorized by difficulty: Easy, Average, and Hard. They are also categorized as Physical or Mental skills, with Very Hard as an option for some Mental skills. Easy skills cost fewer points to purchase levels in, while Hard skills cost more. A player can purchase a skill for his character at any level he or she can afford. The lower you choose the fewer points it costs to buy the skill, and the higher you go, the more points it costs. Some skills have default levels, which indicate the level rating a character has when using that skill untrained (i.e. not purchased). For example, a character with a Dexterity of 12, uses the Climbing skill untrained. Climbing has a default of DX-5 or ST-5, which means that using the skill untrained gives him a Climbing skill level of 7 (12-5) if he tied it to the Dexterity stat. If the character had a higher Strength stat, he could have a better chance of success if they tied the Climbing skill there instead.

Many Skills also have a Tech Level (TL) rating attached to them, to differentiate between Skills that concern similar concepts, but whose tasks are accomplished in different ways when used with differing levels of technology. This helps during time traveling scenarios, or when characters are forced to deal with particularly outdated or advanced equipment. For instance, a modern boat builder's skills will be of less use if he is stuck on a desert island and forced to work with primitive tools and techniques. Thus, the skills he uses are different when in his shop (Shipbuilding/TL 8) and when he is on the island (Shipbuilding/TL 1).

===Success rolls===
GURPS uses six-sided dice for all game mechanics. For instance, if the damage of a weapon says "3d+2" then you'd roll three six-sided dice, add the results of each die together, and add 2 to that result. Likewise, if it said "2d-1", you'd roll only two dice and subtract 1 from the total result. For stat and skill checks, the player always rolls three six-sided dice. Note that this makes a "default" skill check (a skill of 10, based on an unmodified attribute) 50% likely to succeed. 

Making stat and skill checks in GURPS is the reverse of the mechanics of most other RPGs, where the higher the total of the die roll, the better. GURPS players hope to roll as low as possible under the tested stat's rating or skill's level. If the roll is less than or equal to that number, the check succeeds. There is no "target number" or "difficulty rating" set by the Game Master, as would be the case in many other RPG systems. The GM may, however, calculate various modifiers to add or subtract to the die roll. In this way, positive modifiers increase the chance for success by adding to the stat or skill level you must roll under while negative modifiers deduct from it, making things more difficult. 

For example: a player makes a pickpocketing test for her character. The player has assigned a Pickpocket skill with a level of 11. Rolling 3 dice, the result must be 11 or less to succeed. If the player rolls above 11, then her character has failed the attempt at pickpocketing. No matter the level of the skill, a die roll of 18 or 17 is always a failure, and a roll of 3 or 4 is always a success. The Game Master may decide in such cases that, in first case, the character has failed miserably and caused something disastrous to happen or, in the other case, that she succeeds incredibly well and gains some benefit as a result.

===Combat===
Like most other RPGs, combat in GURPS is organized in rounds. A turn is equal to one second of real time. In one second, a player can make her character take an action, such as attack or move. Free actions are simple actions that can be done at any time. Characters in a party have a set initiative every round that is based upon their Speed.

There are two kinds of attacks: Melee (possibly with hand-to-hand weapons) and Ranged (e.g. bows and guns). Attacks made by a character are checked against their skill with the particular weapon they carry. For instance, if a character is attacking with a pistol, it is beneficial to have a high level in the Firearms skill. Like any other skill check, a player must roll equal to or less than the level of the skill to succeed. Failure means a miss, success scores a hit. Similarly, rolls of 3 or 4 are "critical hits", which means the weapon deals its maximal damage to the target. Attack modifiers are set by the GM when factoring in things like body armor and cover.

===Damage and defenses===
Damage from melee weapons, (clubs, swords, daggers, etc.) is calculated based on the character's ST rating. The weaker a character is physically, the less damage he or she is capable of inflicting with a handheld weapon. Ranged weapons have a set damage value for the projectile they fire. When damage is inflicted upon a character, it is deducted from their Hit Points, which are calculated with the Strength stat. Like any other RPG, when characters lose their hit points, they're in trouble. Depending on the nature of the attack, there will sometimes be additional effects. GURPS calculates shock penalties when someone is hit, representing the lasting harm it causes. Different weapons can cause different 'types' of damage, ranging from crushing (a club or mace), impaling (a spear or arrow), cutting (most swords and axes), piercing (bullets), and so on.

===Advancement===
Finally, the most useful award after playing a good session of GURPS are more character points, which can be used to advance the character with enhanced stats, skills, or other goodies. Points are distributed by the GM at the end of each session. Unlike many RPGs, however, players receive no experience for killing monsters. GMs are free to distribute experience as they see fit, but 1-3 points for completing objectives and 1-3 points for good role-playing per game session are considered normal.

Advancement can also come through study, work, or other activities, either during game play or between sessions. In general, 200 hours of study equals one character point. Self-study and on the job experience take more time per character point while high tech teaching aids can reduce the time required. 

Some intensive situations let a character advance quickly, as most waking hours are considered study. For instance, characters traveling through the Amazon may count every waking moment as study of jungle survival, while living in a foreign country could count as eight hours per day of language study or more.