Disclaimer: I backed the Kickstarter campaign for this product and paid for a digital copy, a hard copy, and Hero Lab files. At the time of this review, only the digital copy was released, so that is the only thing this review will consider.
After less time than I expected, it's here - the martial companion to the much-loved Spheres of Power book, whose main tome and later expansions I've been reviewing.
Much like its predecessor, the main goal of Spheres of Might is to replace a system in the game (in this case, martial combat) with something more flexible and fun than trading full attacks with foes. Despite that, it's not necessary for everyone at the table to be using it - there are few truly new mechanics introduced, so it's easy to incorporate both into any given game.
The martial talents presented in this book fall into two categories. Basic talents have no prerequisites and are pretty much all extraordinary abilities, making them suitable for just about any game. Legendary abilities are more supernatural and fantastic in nature, and are only available with GM permission. (This is NOT the same setup as Spheres of Power's Advanced Talents system. Advanced Talents can be game-changing. Legendary Talents, on the martial side, are still broadly within the range of what a character could normally do in Pathfinder. Admittedly, some effects were largely caster-only before, but that's really not a problem here.)
After an introduction that provides some flavor and discusses the goal of the book, the tome moves on to introducing the combat spheres. Like the magical spheres, characters are divided into three progressions: Expert (Full), Adept (Medium), and Proficient (Low). Immediately following this is a conversion table for non-SoM classes, allowing them to exchange certain feats for combat talent progression. In addition, 4th-level/Low Casters can trade their casting for Proficient progression, while 6th-level/Mid Casters can exchange their spells for Adept progression. Full casters cannot exchange their spells (and honestly, that's probably for the best, because they usually have low BAB and wouldn't get much value from this system anyway.)
What this book doesn't have is gish/hybrid classes or options. Those are set to appear in a different book, and aren't part of the core rules here.
Following this, we get to the new terminology. Among the new things introduced is Martial Focus, which will be familiar to people who've used Psionics. Essentially, martial focus is something you can expend to activate certain abilities, or to Take 13 (not 10) on a Fortitude or Reflex saving throw. Some abilities also require you to have it 'on', so it serves as something of a limiter to stop characters from doing too many things at once.
The last bit of the introduction covers some clarifications on rules (including double-barreled weapons, improvised weapons, unarmed attacks, and so forth).
After all of that, we finally get to character creation. The most important part of this is the Martial Tradition, an explanation of how and where a character learned to fight. The book encourages limiting traditions to particular groups as a way of emphasizing their flavor and differences, but that's not actually required.
Martial traditions aren't nearly as optional as casting traditions in Spheres of Power - the new classes expect you to take them, and guidelines for converting non-SoM classes are included. Broadly speaking, though, each tradition offers four talents worth of benefits: Two from the Equipment sphere, a base sphere (or choice between two base spheres), and one additional thematic talent. Simple rules for creating new traditions are included, but mostly come down to "don't focus too much in anything besides Equipment, and don't do solely offense or defense".
Following this is a long list of new traditions, from Animal Trainers to Courtesans to Gladiators. It's a thorough list, and looks like it covers most base concepts.
Next up, we have the classes. These include the Armiger (Full BAB/Low Progression, but gets bonus talents on customized weapons they can rapidly swap between), the Blacksmith (Full BAB/High Progression, improves the party's gear while hitting foes pretty hard), the Commander (Mid BAB/Mid Progression, best for directing and buffing allies), the Conscript (Full BAB/High Progression, effectively Spheres of Might's Incanter in that it's less a class and more a build-your-own-warrior thanks to tons of extra feats and talents), the Scholar (Low BAB/Low Progression, focused around making and using a variety of substances and traps), the Sentinel (Full BAB/High Progression, very much a walking tank who can endure things), the Striker (Full BAB/High Progression, a mobile, risk-taking combatant), and the Technician (Mid BAB/Mid Progression, creates gadgets and inventions, including independent minions).
After this, we get a nice set of archetypes, both for the new classes and many of Paizo's releases. Note that the Archetypes for Paizo's classes are all quite distinct, rather than being pre-made versions of the conversions listed above.
Finally, we get to the Spheres themselves. Much like Spheres of Power, each of the spheres here is focused around a particular concept, such as Alchemy, rapid-fire Barrages, Boxing, or the use of Traps. There are 23 spheres provided - although the Equipment sphere is a little different in that it's mainly a collection of proficiencies. That's not to suggest there's no other value in it, though, because its non-Discipline options can be beneficial for many different character concepts.
One key point to note here: Some Spheres are extremely similar to feats. These are specifically called out, and compatibility is built into the system. You can always take an associated talent instead of the feat (if, say, you got the feat as a bonus from your class), and having the talent counts as having the feat. That's a nice - and important! - touch.
The Legendary (supernatural/magical) talents follow the normal ones, split into their own section to make it easy for a GM to add or remove them from a game. Since many of these have prerequisites - some as high as 20th level - they're not likely to see much use early on.
The rest of the book focuses on the standard extra options for a new system - feats, traits, favored class bonuses, drawbacks, and new pieces of equipment are all included. There's also a GM toolbox (with suggestions for cinematic combat, monster-exclusive talents, example monsters from CR 1 to CR 21, and sample characters if you want to dive right into playing with them.
Starfinder fans get a special treat at the end of the book, with a conversion section meant to work in tandem with the SFCRB's Legacy Conversion chapter.
All in all, I'm extremely happy with this book, and I'm looking forward to a full playtest run. Martial characters just got significantly more interesting - so if your old Fighter is starting to feel a little stale, it might just be time to dive in and try something new. This gets a full 5 stars from me, and I'm eagerly awaiting my physical copy.