Pathfinder Campaign Setting: "Aquatic Adventures" [RPG]

 It's fair to say that aquatic combat is complex and cumbersome to handle in Pathfinder: dealing with the shift to three-dimensions is hard to track on a grid, there are special rules for different types of weapons, the constant need for Swim checks to maneuver (or avoid sinking), tracking of how long a character can hold their breath, and much more.  If it's a situation that only pops up on isolated occasions (diving to the bottom of a pool in a dungeon, for example), many GMs will just handwave it.  But for campaigns set in or around rivers, lakes, and oceans, hand-waving the aquatic combat rules makes aquatic encounters less special, aquatic monsters less threatening, and character options designed for such a situation irrelevant. 

Aquatic Adventures does a great job explaining and supplementing the rules for aquatic encounters as presented in the Core Rulebook.  I'd consider it indispensable for adventures set in places like the River Kingdoms or for something like the Ruins of Azlant adventure path.  Only about a third of the book is rules "crunch", with most of the chapters devoted to crunch-free (but extremely flavourful!) descriptions of the different oceans and seas of Golarion.  I'll go through the chapters one by one, but first, we have to give praise to that amazing cover--that's the sort of thing that should be a poster.  The art is reprinted on the inside back cover, while the inside front cover is a sort of "in-game" map showing the different oceans and seas in the game world (it's startling to remember just how small the Inner Sea region is compared to the rest of Golarion we rarely see).  The overall layout and interior art of the book is very well done.

INTRODUCTION (2 pages)

This is a short, lyrical overview of oceans and their dangers.  There's nothing wrong with it, but it's inessential.

ANTARKOS OCEAN (4 pages)

This is the great southern ocean of Golarion.  The name is a bit too much on the nose, because the "Antarkos Ocean" has freezing waters, the danger of icebergs, fog, and so forth.  The description is very well done, and makes the prospects of exploring the ocean and the ice sheet of the south pole the sort of thing to fill PCs with dread.  There are some great bits of setting lore, like a mysterious race of dream-powered giants and a colony of kalo.  In addition, there are tons of great adventure hooks to explain why the PCs would want to come here in the first place.  

ARCADIAN OCEAN (4 pages)

The Arcadian Ocean separates the continent of Avistan (where most Pathfinder adventures are set) from the rarely-seen continent of Arcadia.  The ocean here is filled with pirates, submerged ruins, and lost magics.  This is where Ruins of Azlant takes place.  Again, a lot of great adventure hooks to explain why PCs would try to cross such treacherous waters.

EMBARAL OCEAN (4 pages)

The Embaral Ocean is a "marine desert", which I didn't realise was a real thing.  There's no aquatic life at all, nor is there any wind or currents to make journeys easier.  It's an interesting idea in concept, though I'd have to see some adventures using it to really get a sense of whether it would work in practice.

OBARI OCEAN (4 pages)

The Obari Ocean borders Casmaron (and Vudra), and features occasional terrible storms.  At this point, I notice that it's hard for the writers to make descriptions of different oceans sound interesting--"water be water", after all.  There's something about an ice forest which sounds like a cool concept.

OKAIYO OCEAN (4 pages)

This is a pretty standard ocean, distinctive only by the presence of a mighty sahuagin empire.

GOLARION'S SEAS (18 pages)

This section includes two pages each on the following seas: the Castrovin, the Fever, the Inner, the Ivory, the Shining, the Sightless, the Songil, the Steaming, and the Valashmai.  Each entry includes a brief summary, then longer passages on characteristics, denizens, treasures, and a notable geographical feature.  It might sound bland, but there's a lot of exciting ideas here like the Razored Labyrinth of the Castrovin Sea (a maze of rocks sure to sink any ship that tries to pass through without a map) or the epic kaiju (and more) of the Valashmai Sea.  Devotees of the Inner Sea will find a bit on different countries' navies.

AQUATIC RULES (22 pages)

As I mentioned in the opening, this section is indispensable.  It contains clarifications and additions for things like buoyancy, fighting underwater, how various types of spells function, Perception and Survival checks, drowning, pressure and temperature, and more.  If you want to do underwater combat well, this section will answer most of your questions.  It contains some advice on "thinking in three dimensions", though I'd suggest this may be a trial-and-error thing for most groups.  The section also includes several new archetypes and class options--most of them are really good at making underwater exploration and combat more feasible for PCs.  For example, there's an "aquanaut" archetype for fighters, an "underwater" combat style for rangers, lots of good mundane equipment, the "aquadynamic focus" feat, and some great spells like free swim and lead anchor (potentially really nasty!).  Melee characters will appreciate the underwater special weapon ability.  There's a ton of new options here, and the vast majority are solid in terms of power versus cost.

And that's Aquatic Adventures.  It's one of those books that's easy to overlook until some goober falls off a bridge, tips over a canoe, or decides to become a pirate--but when you need it, you really need it.