The first thing one notices is that the Autarch people seem to be mantaining the excellent production values we saw with the ACKS core rulebook. The cover is beautiful, the B&W illos inside are great, the layout is still clear, and the PDF is well annotated. I wonder what the physical book is going to look like, but if the PDF is any indication it should be pretty good.
The biggest chapter is right upfront, the 18 new Character Classes. Let me preface this by saying that I have the weirdest love/hate relationship with character classes. On one hand, I like broadly-encompassing, archetypal character classes because they make my life as a GM easier. Barbaric berserker? Fighter. High-and-mighty knight? Fighter. Scruffy mercenary? Fighter. Disciplined legionnaire? You get the idea. On the other hand, having a smorgasbord of character classes to choose from appeals to me on a visceral, fat-kid-in-a-candy-store level, because even as a GM I vicariously enjoy my players' excitement at the new toys; and on another level, as a GM who’s into building and running worlds that behave reasonably like our own, because broadly defined classes inevitably require some handwaving; one recurring issue back in the day, playing TSR-era D&D was the Fighter in light armor – while it could be situationally useful (e.g. when stealth is called for, when you're at sea, or when the climate is very hot), in most situations the system didn't reward you for playing a nimble, lightly-armored melee combatant. And don't get me started on Clerics and polytheism! Having specific classes for certain “corner cases” that exist in fiction but I feel aren’t adequately covered by D&D's usual archetypes can be very appealing.
Most new classes are human classes. We have well-loved classics like the Paladin, the Barbarian, the Mystic (monk) and the Shaman (druid), and plenty of novelty. There’s the Nobiran Wonderworker that's supposed to be a mixed arcane and divine caster with divine or angelic blood (think demigods, Nephilim and Aasimar here). There's a Priestess that's effectively a divine "pure caster", i.e. a cleric minus armor and several weapon selections; do away with the gender restriction and you have a decent all-purpose non-combatant divine spellcaster. There's a Warlock with interesting and flavorful mechanical bits, but that mostly reads as “mage, plus extra evil on top” (not that this is a bad thing). There's a Witch that feels fairly fairy-taley but which I had a hard time placing on the game world. The Venturer is a merchant-adventurer type that inexplicably (to me) gains spellcasting abilities at high levels (granted, they gain their first spell at 8th level, but I'd rather give them something like the bard's “charm person on a 11+ roll on 1d20” at 1st level and be done with it). The Thrassian Gladiator is big lizard-man slave-warrior from the default setting’s decadent sorcerous empire. And the Zaharan Ruinguard gives the Anti-Paladin a run for his money and further clogs the market for evil spellcasting black knights; they're not quite identical, but occupy the same niche in my eyes.
Of course, demihumans haven't been left out. Elves get the bard-like Elven Courtier, the sorcerous Elven Enchanter and the inevitable Elven Ranger. The Dwarven Delver is pretty much a dwarf thief with an emphasis on dungeoneering and I love it. The Dwarven Fury and the Dwarven Machinist look fun to play, if a tad more WFRP-ish than I generally prefer my dwarves. There's also a Gnomish Trickster, which is okay, I guess; I’d still rather have a Halfling Burglar, but maybe it’s just a matter of reskinning or minor alterations.
Next we have tables of Templates. Templates are ready-made “kits” for each class that pairs an evocative name (e.g. Corsair, for the Fighter) with a preset choices of Proficiencies (in this case, Seafaring and Swashbuckling) and a gear list (leather armor, scimitar, colorful tunic, silk sash, etc.). Useful for those who want to whip up a 1st-level PC or NPC in little time; and better still, nicely arranged in random tables. There are also a couple of gamer culture Easter eggs and some very subtle humor hidden in the entries (PM me if you can't spot them and I'll tell you).
The following chapter lays bare the guts of the ACKS class system and offers extensive guidelines on building and balancing new character classes, that is validated by reconstructing the very classes presented in this book. Now, I confess to not being a huge rules guy, but what jumps to attention is the level of attention given to it. I know of no version of D&D that ever offered such precise and voluminous guidelines to do-it-yourself class creation. I found the specific guidelines on racial character classes particularly interesting, as they pave the way to come up with race-specific versions of just about every character class, though at that point one might as well play AD&D with select ACKS subsystems tacked on for good measure.
Magic is the theme of the next chapter. First we are given expanded rules on magical research and experimentation, complete with random tables for sorcerous mishaps, and sub-tables for magical mutations and spell signatures borne of mishaps that wouldn’t look out of place in the DCC RPG. And what follows is the inescapable list of new spells, which includes Rituals (arcane level 7-9 spells and divine level 6-7 spells, which, ACKS being capped at level 14, require ceremonial magical effort to cast). Some of the spells are a bit more over-the-top than I usually prefer (call dragon? Really?) and some make you wonder why is it that you've never seen them in a D&D rulebook before (can’t believe we had to wait over 30 years for a choking grip spell), but most are traditional D&D fare like cone of cold or spider climb. Detailed rules for creating and balancing new spells are given as well.
The book rounds up with a “supplemental rules” chapter that provides guidelines for character aging, short lists of new equipment and new Proficiencies, and random tables for followers.
Page-count-wise, the meat of the book is the new classes, and like I mentioned in the beginning, I'm somewhat ambivalent towards it. Nevertheless, even placing aside the new classes (some of which I loved, some of which I didn't care for) and the class-building guidelines (which deserve a bit more attention and scrutiny on the reader’s part, but superficially look like a godsend to the DIY enthusiast GM), the expanded magical research rules scream “play with me!” and the last chapter's notes on aging and followers should have been on the ACKS book (probably cut out for space).
If you're running ACKS and you want new classes, or if you're really really into DIY classes and spells, this is a must-buy. If you're not running ACKS… I'm not sure. Maybe some of the new classes can be made to work with B/X or BECMI/RC and similars, but some tweaking will definitely be necessary.