In essence, this is a cut-down version of the core rulebook containing material of use to a player, with extensive notes on how the 2D20 game mechanic works and everything you need to generate a character using the detailed 'lifepath' system designed for this game. Given the sheer size of the core rulebook, this makes some sense, but it does leave out quite a lot of the setting background as well - stuff that a character would know, even if his player does not. If your intent is to play and never GM this game, and cost/portability is important, it's a good option.
The Introduction begins with general notes on the setting and the tone of the game, then presents an overview of the inhabited planets in the Human Sphere and the factions of the future - as despite technological advances and rises in living standards, human beings seem as quarrelsome as ever. We also hear about the Combined Army, an AI-led group of alien races who are at war with the Human Sphere, attacking at any opportunity, as well as a couple of the major alien races involved.
Next comes a section on Life in the Human Sphere which presents an overview of everyday life. While not everything is wonderful for everybody, it is the case that the bulk of economic activity is directed at fulfilling desires rather than meeting basic needs. Quite a bit of space is devoted to explaining Maya - the successor to the Internet - and the way in which information and communications are handled seamlessly and immersively, with artificial reality (AR) playing a large part. It's a mesh-based system (everything connected with everything else) with integral encryption and tracking based on 'hyperledgers', which are the successors to blockchains and probably as little understood by the average citizen! It is so pervasive that it's unthinkable for the lights not to come on when you enter a darkened room (OK, so that already happens in my office at university, even if that it merely a motion sensor!), but the idea that you could query the drink you put down a few minutes ago as to precisely where you left it appeals. Travel between the colonised planets is effected by wormhole, there are some notes on that as well as on popular spectator sports and much more.
The next discussion covers the nature of the games you'll play. The default is that characters are agents of the Bureau Noir, the 'secret service' of an organisation called O-12 that exists to maintain some level of peaceful cooperation across the Human Sphere. Within that, however, many individuals hold allegiance to one of the factions and often find faction errands piggybacked onto a Bureau-assigned mission. Of course, outside of this there are no end of adventures to be had if you prefer to go exploring or trading, join the military, or work more overtly for your faction in some manner.
We now move on to more detailed analysis of 2D20 game mechanics. This - and the following sections on character creation - are as detailed as the core rulebook versions, so if game mechanics rather than setting are most important for you, you will not lose out by getting the Player's Guide rather than the full rulebook. The cinematic nature of the 2D20 system is explained well, with the use of Heat (for the GM) and Momentum (for players) providing extra edges and drama to proceedings. There's a lot to take in, but once you understand it (and have run through the odd skirmish and other tasks) it's logical enough that things will fall into place. An added dimension is that combat comes in three types (which can run concurrently): actual brawling, infowar and psychological warfare. This can get confusing at first, but as it becomes familiar it's extremely powerful and quite fascinating.
Next we meet the Lifepath system, which creates well-rounded characters with a ready-made background. This system begins with the character's birth and tracks through what happens to them right up to when play begins. Mechanically, there are nine Decision Points that shape his life - but you have five 'Life Points' to guide him through the slings and arrows of outrageous fortune. You end up with a personal background that - like your own - is shaped partly by chance and partly by the decisions that you make. It all begins with determining initial abilities, then the faction and planet where you were born, and your family's status there. After a 'youth event' you gain an education, go through an 'adolescent event' and go through one to three career phases, before putting the finishing touches to your career. There are random tables for each of these, but you may use your Life Points to make choices for some of them - with five Life Points and nine Decision Points you won't be able to choose everything, so decide what's vital to the character you want. An elegant system which can provide hours of endless fun... a good idea, as you don't knock out characters that quickly with such a system, so have a few in your folder ready just in case you need one mid-game! However, as resurrection is now possible, you might not need that.
Loads of detail about each stage is provide to help you understand everything you need to know. All through this process, you gain skills and traits just as in any character generation process. Some you choose specifically, others come associated with the choices you make or what life throws at you. There is also an alternative point-buy system which, with the GM's permission, you can use to custom-design a character without any random elements. Nice if you have a very detailed character concept in mind, but the random element does make for a more interesting character! Just reading through all the tables spawns many ideas for characters... and should give the GM plenty of plot material for when your past catches up with you! This is followed by details of how to improve a character and extensive notes on all the skills available.
A cut-down version of the information provided in the core rulebook about equipment follows, and then there are two appendices. The first contains information about 'agent handlers' - if you work for a faction, who tells you what it needs you to do? Find out here. The other appendix contains all you need to convert your Infinity RPG character into one playable in the Corvus Belli miniatures skirmish game on which the RPG is based (or, of course, the other way).
A useful abstraction of the full core rules for players, but missing an awful lot of the background information that really brings the setting to life - it's more like the setting information in the Quickstart coupled with the rules fully-expanded from that to the complete ruleset. Useful, however, if you want the game mechanics concentrated in one convenient package.