Designer's Notes: GURPS Fourth Edition

by David L. Pulver

Sean Punch and I started with copies of Basic Set and the two Compendiums. We assembled an enormous outline and an overall line plan, and sent it to Steve Jackson and Andrew Hackard. After they approved it, we went to work. The theoretical division of labor in GURPS Fourth Edition was that Sean worked on Book 1 and I handled Book 2. In practice, that broke down almost immediately, and we both ended up working on a large chunk of each book.

The actual process of writing and revision began around September 2002. For several months, I lived, ate, and breathed "Basic Set." I remember being so focused on it that a few times when I was riding the bus or out at a supermarket filling the cart with canned tuna, I might be hit by an idea and use my cell to phone Sean to discuss it (carefully avoiding those giveaway words "Fourth Edition" in case any gamers might be lurking by the Pocky in the next aisle).

To this end, the chapters I spent most time on in Book 1 were parts of the Advantages and the Disadvantages chapter (focusing mostly on Innate Attack and various exotic abilities), and the Equipment, Psi, and Templates chapters. In Book 2, I worked on Combat, Tactical Combat, Special Combat Situations, Injuries, and the Charts and Tables, and the Infinity setting, along with parts of Animals and Monsters and Technology.

Anyway, several hundred dollars in phone bills later, our labors culminated at the end of March in a frenzied 36-hour no-sleep session to meet our deadline. I remember emailing Sean the last section I was working on -- the Infinity Unlimited background -- just ahead of the clock. We handed in a first draft for April 1, 2003, which was duly announced in the Daily Illuminator by SJ Games (with some minor disinformation about content). Then we got some sleep.

The GURPS Fourth Edition playtest began in early summer of 2003, and involved a select group of many dozens of active and not-so-active GURPS contributors. It was almost as wild as most Pyramid playtests, and numerous ideas were suggested and thrashed out -- in particular, I remember some very productive discussions on how tech levels should be handled, a huge threaded discussion on how Allies and Patrons should work, and some heated debate on the nature of Strength and Hit Points, and strong lobby in favor of keeping the parachronic secret from Reich 5, all of which led to significant revision. During this period, I worked with Sean on revising some of the chapters, and this progress continued through the fall of 2003. Then Sean, and later Andrew and Steve, worked on perfecting the final draft for months after that.

In addition to the goals established by Sean and Steve in the outline and the many individual fixes (we had hundreds compiled from years of Q&A), there were three things I especially wanted the revision to accomplish.

The first was to make combat play faster without losing its tactical feel. For me, the two most important ways to do that were to simplify ranged combat and make changes to the way Active Defense worked.

The second was to make it easier to play both high-powered games to slay the old "GURPS doesn't do Supers well" canard. However, this meant not just supers, but also robots, vehicles, big guns, and even bigger explosions. Near the top of the list was fixing rules like the unbalanced cost relationship between Hit Points and DR, and ensuring the system properly handled various high-powered abilities, including -- but not limited to -- attacks.

The third was to ensure that we connected the dots between the various "subsystems" in GURPS. This meant that, for example, super powers, missile spells, and high tech weapons all used the same rules for handling things like explosions, or that the incomes for jobs interfaced with starting wealth and status-based cost of living at various TLs. In other words, system unification, or functional simplicity.


Combat was divided into three parts, rather than the old Basic/Advanced split. In GURPS Fourth Edition, the "Combat" chapter covers most situations, including things glossed over in Basic Combat in the last edition, such as automatic fire, close combat, and movement. We now make the assumption that GMs can visualize spatial relationships (or scribble a few notes down on a map). Thus, ranges and movement are integrated into them. "Tactical Combat" is the rules for hex grid action and only that. As a result, it's much more focused. "Special Combat Situations" is what it says: a grab bag of situation specific or optional rules covering a range from hit location and cinematic combat to explosions.

The removal of Passive Defense (except, effectively, for shields) and replacing it with a flat +3 increase in defense rolls was probably the most obvious change made in the combat game mechanics. There were many realistic reasons for removing it, as the various "special case" PD rules that crept into places like High-Tech attest to. But the biggest one was flavor. When an armored knight and a lithe barbarian, both with Broadsword-16, are engaged in a fight, the knight already has a big advantage from his DR 4 chainmail. Giving him Parry-11 and the barbarian Parry-8 on top of that was overkill. So now both have Parry-11. The result is a fight in which every parry really is a parry. The fact that some armor does have a degree of slope or curvature that make it better at deflecting blows is part of its DR.

A question that is often asked is why we did not go with a Quick Contest of Skills for combat. This had some appeal, but it gives too much of an advantage to a higher skilled fighter, and simply doesn't reflect the way fights in fiction or fact between equal foes are usually described. With both Third Edition and Fourth Edition rules, a battle between two master swordsmen will go on longer than a fight between novices . . . which is definitely intentional. Of course, two warriors can still run at each other to make All Out or Move and Attack maneuvers (as is the case in, say, the classic samurai movie duel).

Now, one problem with the existing rules as applied in Third Edition was that a fight between two highly skilled foes with lots of PD could drag on, being resolved only by feints or who scored a critical hit first . . . especially if using advanced combat with the rules for retreating, which gave a +3 bonus (a rule that was originally intended to allow unarmored swordsmen to have a chance at survival). In GURPS Fourth Edition this bonus is reduced to +1 . . . unless using a skill in which fast footwork and mobility are emphasized, such as Boxing, Rapier, or Karate, where the +3 bonus replaces the old 2/3rds skill parry those combatants had, ensuring that people with these skills can continue to defend well despite lack of armor . . . if they have room to maneuver. Back them up in a corner, and the fellow with the big heavy weapon may make mincemeat of them. In addition to this, Fourth Edition also presents other tactics beyond the Feint maneuver that let skilled fighters make the best use of their high skills rules for deceptive attacks and rapid strikes, for example.

A Unified System

A significant goal for GURPS Fourth Edition was to establish a useful "grammar" that further books could expand on. That meant not just including "basic" statistics (like some examples of vehicles or animals or weapons) but establishing a way of describing some things, so that a future GURPS supplement or adventure could simply say "this is a missile launcher with these stats" or "this is a poison with these stats" rather than having to reprint a whole mess of specialized rules from a supplement about how to use these things. So, for example, the injuries section has a unified system for describing poisons/diseases/drugs -- and one that ties in with the character creation system, if you want your character to be capable of delivering them. Similarly, while there are a few dozen vehicle statistics in Fourth Edition, what is far more important is that the book presents and explains the standard GURPS Fourth Edition statistics format for describing vehicles.

For example, vehicles now have a standard statistic line just like weapons. And unlike previous one-line vehicle entries, this line now packs in all the vital combat, capacity, and travel information, from hit points and acceleration to cargo capacity and hit locations. GURPS Vehicles will include the rules for super-detailed vehicle descriptions for situations when it is vital to know exactly what equipment is built into that M1 Abrams or a Free Trader starship.

High-Powered Games

I started out working on Book 1 in the Characters and Psionics chapter. While Sean covered the mass of character creation, my role was often to explore the end points. GURPS evolved from a system that handled medieval combat to one that has let you play angels, dolphins, ogres, Ogres Mark IIIs, ghosts, demi-gods, and disembodied computers, and people who can download software into their brains. In so doing, many rules had to be tacked on top of other things, and many square pegs forced into round holes. One of the great things about working on a new edition of Basic Set was that we both had the benefit of hindsight. We knew what areas had given problems to world book authors in the past, and where possible, designed around it. This let us to use elegant solutions. For example, we figured out that the rules for gods needing worshippers and trucks needing gasoline were basically the same Disadvantage, and wrote it as such.

The aforementioned goal of system unification was followed in the psionics system, which emerged as a prototype for the way a wide range of special abilities are handled in the upcoming GURPS Powers. Another issue was the vexed question of paying character points for devices, vehicles, and so on. I don't like doing this in many games, but I do feel the option should exist where appropriate, such as a supers or anime-themed game, where one hero might be a chi-powered martial artist, another can turn into a living fire elemental, and a third rides a giant robot, and the fourth is a gun-packing vigilante with an armored van full of weapons. In the past there was no way to easily calculate this. My goal was to ensure that most technologies had an equivalent advantage -- both to ensure that you could easily build robots and cyborgs and super-inventors, and to make it possible to succinctly describe both with the same set of rules.

My own experience with books like Transhuman Space and Bio-Tech (and on Sean's part, Undead) showed us some things Third Edition had trouble with. For example, robot, spirit, or animal characters often had the same unwieldy laundry lists of advantages and disadvantages. This led to the metatrait system: pre-designed "packages" of advantages and disadvantages that set down canonical (but easily customizable) values for things like animal intelligence or machine bodies or being a ghost.

Into Infinity

Another reason why both high powered settings system unification were important to me was the decision to include the Infinity setting within the game as a ready-to-use example of a multi-genre campaign setting . . .

This was the last part of the Basic Set that I worked on. I liked it when it was introduced in Time Travel and had used it myself as the setting for my "Soulburner" adventure in Time Travel Adventures which introduced the world of Technomancer. In Fourth Edition, I wanted to "blow open" the basic Centrum-Infinity struggle by adding multiple factions and multiple means of dimensional travel, new groups such as the ISWAT black ops team, the Reality Liberation Front, and new features such as the parachronozoids, nexus portals, shiftrealms, the infinity-spanning chronobahn, and pocket multiverses. It's a short chapter, but I was quite pleased with it, and hope it will encourage people to give the Infinity setting a try; it's not just Centrum versus Infinity any more, although that framework certainly still exists.

Working on GURPS Fourth Edition was a culmination of several years of writing for Steve Jackson Games. I'd like to thank Steve for having created such a fascinating and versatile system, Andrew and Sean for having given me the opportunity to play with it, the other GURPS authors for the numerous books and articles we were able to draw upon, and everyone on Pyramid whose comments have been helpful, critical or supportive, and whose enthusiasm has helped keep me going over these years.

Article publication date: July 30, 2004

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