This pdf is 32 pages long, 1 page front cover, 1 page editorial, 1 page ToC, 1 page advertisement and 1 page SRD, leaving 27 pages of content, so let's check this out!
First, you'll have to indulge in a little bit of vanity on my part - I joined the kickstarter for alternate objectives and the rapier-wielding guy on the walkway across lava in the first piece of b/w-artwork? Well, that's me. Great rendition and rather close to the original, if I may say so. That piece of idle ego of yours truly out of the way, let's see whether this toolkit lives up to my steep expectations. So what exactly does this provide?
This pdf is essentially a DM's toolkit to making the terrain count in your encounters and thus starts with a discussion of different effects of terrain - from obstructions, to movement-altering properties, damaging, healing and even boon-granting terrain-types are mentioned. Next, options to change the terrain are covered - from activating terrain to one that can be destroyed and triggered ad then even moving terrain is covered - as is portable and spreading terrain. Special mention deserves the massive table on terrain damage by level and DCs, making the rafting of your very own damaging terrain easy indeed and just a matter of taking a single glance.
These basic concepts and discussions out of the way, we take a look at different terrain special abilities and oh boy, the list is neat: From Acid Rain to an Arcane Ballista, we're in for fun: Placing and using the respective terrain pieces is easy and we're in for a neat design decision: The terrains use their own atk-bonus in order to enable the maximum number of PCs to use them, but also provides guidelines to enable you as a DM to use the PC's capabilities when utilizing terrain. But hat's not all - the Blood Mage's Circle lets PCs sacrifice HP for empowered magic, while chaos motes can deals random energy damage and spirit circles can make incorporeal spirits corporeal. Add conveyor belts, crumbling walls and dimensional rifts that teleport people entering them, add exploding kegs, swamps erupting in flames, jump-pad like stones that let you temporarily fly, floating stones, floors sans friction, giant cogs to make clocktower battle-scenes, grasping zombie claws from the floor, divine blood, variations of holy light/gloom, flammable oil, and lifting pillars (including a special maneuver to have foes attack the pillar, potentially collapsing it) up to mine cart rides, deadly mushrooms and even shattering glass, we are in for a wild ride.
Have I mentioned sleep poppies and the river of dreams and the ability to proverbially draw the weapon of kings, Excalibur-style, from the stone? What about more standard spiked floors, tugging rugs from under the feet of opponents, weak floors, trick staircases and even the option to treat walls and ceiling as ground, making battles 3-dimensional -awesome!
The pdf concludes with a list of terrains by location.
Editing and formatting are very good, I didn't notice any significant glitches. Layout adheres to a 2-column b/w-standard with some neat pieces of b/w-artworks. The pdf has no bookmarks, which is a bummer, as it impedes the otherwise stellar usability of the pdf. That being said, you should print out this pdf anyways - this toolbox of awesome terrain features is a GODSEND to DMs.
To all DMs of 3.5 and Pathfinder, to everyone sick and tired of boring encounters, to every DM out there that seeks to add spice to his encounters, to any group out there: If you're tired of encounters being just about the same types of terrain, about the same weather and combat options, this is the end to your woes. Humble to the extreme, the Terrain Toolbox is simply one of the best and most useful DM-tools released so far for PFRPG and BELONGS into any DM's arsenal. The guidelines towards the creation of your own terrain complement the stellar examples of cool options to spice up your encounters and the fun truly begins once you start to combine the features - flight stones, thought floors and perhaps a chaos mote or two and we're in for an otherwise unremarkable encounter turned into a mind-boggling experience guaranteed to have your players talking about the battle for years to come.
A dungeon created with this book will be almost guaranteed to be vastly superior to one created sans this pdf. Add to that the low price and we have a pdf that you definitely have no reason whatsoever not to purchase. In fact, I'd urge Paizo, if/when they ever create a second GM-guide to create a chapter devoted to such terrain features. Yes. It's that good. I rarely encounter a pdf I can so universally recommend to just about all GMs out there and remain only with two complaints - first, the lack of bookmarks SUCKS. Especially for such a useful product that will see a lot of use. Secondly, I so would have wanted this pdf to be triple the length - we need sequels. Seeing how one complaint isn't enough to rate this down, I'll remain with a final verdict of 5 stars, but withhold my seal of approval until bookmarks have been added. That being said: Get this. Seriously. You won't regret it.