YAGS is a set of Free RPG rules, and all of it can be downloaded from the links below. The rules are released under the GNU GPL version 2, and may be modified and re-distributed either commercially or non-commercially as per that license.
The basic rule system has tried to keep things simple (though not as simple as some people may like). More detailed rules covering specific topics will become available as individual articles as and when they are ready. This will include such topics as computer hacking, wilderness survival, psi and similar topics. Some of these articles may be a couple of pages, others could be much longer.
The downloads here are the official releases, but are not necessarily the most uptodate versions. More recent versions can often be found on GitHub, which are generated directly from the source. However, they may be in an incomplete state.
The core system provides a generic framework on which YAGS is based. All the rules here are setting neutral, though they are biased towards near-modern settings.
Core Rules. These provide an introduction to the YAGS game system, and should be consistent across all settings and genres. They do not contain anything about character generation or combat, but instead contain the basic framework which is common to the rest of YAGS. The system is designed so that extra setting specific modules can be bolted onto the side of these Core Rules to provide a customised version of YAGS for a given game.
Character Generation. How to generate a character using the standard rules. These rules are biased to near-modern settings, though this is mostly due to the selection of skills rather than because of any hard and fast rules. Most other settings will be similar to this, but with extra features around the edges. These basic character generation rules use a point based approach to building characters, with no limitations based on classes or templates. There is no reason why a completely different method of character generation couldn't be done however if the setting called for it.
Combat Rules. These define how combat works, from punches and swords to rifles and grenades. Combat can be relatively deadly, though tries to allow for a reasonable chance of 'dying' results rather than outright death. These rules are meant to be comprehensive, and will probably grow over time, however they are focused on character to character scale combat - combat between vehicles or space ships are left to a different module.
Bestiary. A list of animals and monsters together with their descriptions and statistics for YAGS.
High Tech. Some simple equipment lists for weapons and vehicles from TL6 to TL8 - i.e. the 20th century. This is currently a basic list which will be fleshed out over time.
Character Sheet. A sample character sheet.
These are some generic science fiction rules which include skills and backgrounds which are not so common in modern or historical settings. A particular type of setting is assumed, where society is reasonably similar to that of today, except it happens to span a Galactic Empire of thousands of worlds. It is similar to settings such as Traveller or Babylon 5 in terms of technology and possibilities.
SF Character Generation. Rules on generating characters in a Galactic Empire style science fiction setting, including skills and backgrounds available only in a futuristic society.
SciFi Tech. A look at the technologies of SciFi campaign settings, from TL 9 onwards. SciFi is relatively soft, assuming a setting where star travel is common against a backdrop of galactic empires, aliens and laser weapons.
Habisfern is a fantasy campaign setting designed for use with YAGS. It is a low fantasy setting, in a world that has recently come out of an Ice Age where the Ice is still seen as a major threat to human civilisation.
Habisfern Character Generation. An introduction to the Habisfern Fantasy Campaign Setting, together with rules for generating characters for that campaign. Characters in Habisfern have more priorities to select during generation, including bloodline and social class as well as the usual attributes, skills and advantages. Characters also have a choice of templates, which provide a small set of starting skills as well as description of your place in society.
Rune Magic. Wizards get their power from studying the Mysteries, which allow them to learn runes which enable them to shape the world around them. Rune Magic is the type of magic most common in the lands of Euressa.