What are the differences between the various editions of GURPS?

Question

What are the significant differences between GURPS 4th edition and earlier editions?

The recent spate of GURPS questions have piqued my curiosity, and the system looks like it would suit a campaign I'm planning that would start with a world-generation session using a game of Microscope. GURPS looks like it can handle anything the group could possibly create during the Microscope session.

I'm likely to use GURPS 4th edition since that's the most recently-published edition, but I'm not shy about using older editions of games if they suit my tastes better. Having no prior experience with GURPS, I'd like to know a bit more about the history of the editions and the changes they've introduced before I invest in a particular edition's books.

I'm hoping that this question will be generally useful for people wondering about the differences between editions, not just useful for my particular situation. I deliberately didn't phrase this as a system-recommendation question for that reason (though recommendations are not an unwelcome bonus!).

Answer 1

First of all, let me address an important fact:

The core of the system has stayed the same. They're all point-buy character creation systems devoid of classes and levels. They're all skill-based. They all feature 3d6 roll-under task resolution. They all have an extensive collections of Advantages, Disadvantages, and Skills. They all have combat that scales from basic and abstract to advanced and tactical. They all feature 4 character attributes:

• Strength (ST)
• Dexterity (DX)
• Health (HT)
• Intelligence (IQ)

All are built to handle any genre, any character, and any situation you can come up with.

Differences

I'm going to limit my answers to the differences between 3rd and 4th editions, because I assume those are the ones you're really asking about.

3rd Edition had hit points were based on Health, fatigue based on Strength.

4th Edition reverses that.

3rd Edition attributes were all purchased on the same graduated scale of point costs that made mid-range scores cheap, and high-range scores expensive.

4th Edition attributes are purchased on two separate scales (one for, IIRC, DX and IQ; the other for ST and HT) with constant steps between scores.

3rd Edition was a very solid edition, but had certain problems. Probably the most talked about were IQ-related. For example:

• It was impossible to have an intelligent character that spoke a foreign language badly.
• Intelligent characters tended to be able to avoid the effects of mental disadvantages with ease.

4th Edition addresses those and similar issues. Usually, the fixes are integrations of rules that saw years of use and testing under 3rd edition.

3rd Edition also had a huge library of support books. But that meant that rules were scattered all over those books. At the very least, you needed the Basic Set and the two Compendia.

4th Edition has all the base rules in just the two Basic Set books - Characters and Campaigns. The support library for 4th Edition is smaller, but characteristically excellent. And the vast majority of 3rd edition material can be used with 4th.

3rd Edition had a solid implementation of variable damage types - Crushing, Cutting, and Impaling.

4th Edition damage has been expanded to include even more types, whose effects and even names escape me at the moment. But suffice it to say, in GURPS you'll never have that problem where a .45 and a battleaxe have approximately the same effect.

Conclusion

If you're looking for a recommendation, that's easy. Go with 4th. It's a finely-honed realization of the promise of GURPS - Any genre, any adventure. You can use most 3rd Edition books (many of which are available as PDFs from e23), and the 4th Edition library covers most of the major bases at this point - Fantasy, Space, Supers, Time / Dimensional Travel, Mysteries, etc.

Answer 2

Check out this post on SJ Games Forums for a list of some.

Also this post on RPG.net for a list of changes looking backwards.

Some of the basic/major changes they list:

• In 4th edition, the cost of each additional point in a stat (ST, DX, IQ, HT) does not change. In 3rd edition, basic stats had increasing cost as the stat went up (each point of ST costs more than the last).
• FP (fatigue points - which you lose from heat, combat, and other strenuous activities) is based on HT (health) in 4e, while they are based on ST (strength) in 3e.
• HP (hit points - durability) is based on ST in 4e, but HT in 3e.
• In 4e, all skills have the same cost progression (1, 2, 4, 8, 12, 16, 20, etc) instead of 3e, where there are different progressions for mental vs physical skills.
• Mental disadvantages use a "self-control roll" in 4e, instead of a will roll in 3e. This is to enable intelligent or strong-willed characters still crave candy bars (or whatever). It also prevents a character with strong will to min/max by taking a bunch of mental disadvantages that will never effect them.
• The Psionics system is advantage-based in 4e, instead of skill-based in 3e. Some of the others are more clear-cut to me, but this one seems like a matter of preference. Unfortunately, I can't find a source for this at the moment, but the general consensus is that Psionics were "unbalanced" (too powerful) in 3e, but that a lot of people liked that system better.

Answer 3

The differences between 1st/2nd amount to errata fixes; both were dual booklet boxed sets. The most visible difference of 2nd was cardstock covers on the books.

The relationship of points and abilities was explicitly based upon 250 hours of instruction per point; this lead to the same skill being different difficulties in certain setting books versus others. This was especially notable for paranormal abilities.

The difference between 2nd and 3rd was more profound, with the single large core rulebook replacing the dual booklets of 1st and 2nd ed.

However, there was a profound change in approach to supplements around the same time as the move to 3rd Edition… points went from being different by setting to the same in all settings, breaking the learning curve/points relationship, but making it more universal.

3Rev was more errata, and some new skills/ads/disads from OOP supplements, all bound into the back. The actual rulebook was not retypeset, according to my 3Rev rulebook; this was a cost saving measure (the same plates could be used, and it was a folio longer).

(Added as answer and expanded per request)

Answer 4

There is one big difference between 4e and 3e in how they handle Psionics.

In 3e Psionics is broken down between powers and skills. The power is the overall strength of that line of psionics, like ESP or whatever. The skill is then the individual ability that falls under that power, and represents how much control you have over that area of influence.

In 4e it's simplified down to just individual advantages under the same power categories. (Based only on what I've seen in the basic books I don't know if they expand them at all in expansion books.)

3e Gives a better structure to the Psionics abilities and is more detailed in my opinion.