As much of a fan of GURPS as I am, I do realize GURPS has a certain... well... reputation for complexity. And it is undeserved. That not to say that GURPS doesn't have a hurdle to overcome but complexity doesn't have to be one of them.
The heart of GURPS is found in the free GURPS Lite PDF. It 32 pages and every rule in there is used in a normal GURPS Campaign. The devil for GURPS is in the details, literally. GURPS has a LOT of details. Coupled with that is the fact the GURPS core rulebook are a toolkit. Note if you want to get a taste of the Magic System look at the GURPS Lite 3rd Edition. And if you don't read English well, take your pick of the language of your choice.
To use GURPS you need to choose which options you are going to use to run your campaign. Most of the options are not particularly complex but SJ Games takes the Generic in GURPS very seriously and GURPS 4th edition is a system that literally can handle any type of genre. However the toolkit aspect doesn't appeal to everybody and therein is why GURPS has the reputation it does.
What SJ Games has done in recent years to mitigate this is through their e23 store offer PDFs that IMPLEMENT GURPS for various popular genres. The Dungeon Fantasy series implements GURPS for dungeon crawling. Monster Hunters allows you to play Buffy/Supernatural/Angel/Fringe style campaigns.There is a bunch of them.
If you want to learn to run a GURPS fantasy campaign having played D&D or another fantasy RPG I recommend the following
GURPS Lite 4th edition
The two GURPS Core Book
GURPS Magic 4th edition
Dungeon Fantasy 1,2, and 3.
If the toolkit nature of GURPS doesn't bother you then you can go
GURPS Lite 4th edition
The two GURPS Core Book
GURPS Magic 4th edition
GURPS Fantasy 4th edition
Beyond this you can pick up GURPS Banestorm not so much for its Yrth setting but for all the templates, creature, and character info.
The foremention Dungeon Fantasy Series
GURPS Thaumatology gives you more variant for Magic, some unique some building on GURPS Magic.
If you like detailed combat, then look no further than GURPS Martial Arts.
GURPS Low Tech has the low down on all the mundane stuff of the medieval world. The follow-on PDFs gets into social and cultural details.
Not even you don't want to use GURPS, Low Tech is a great summary of pre-industrial technology.
Anyway I hope some of you get to try GURPS
Diecast #17: The Citizen Kane of Podcasts
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