While I haven't quite finished the entire book, I really enjoyed this so far. It's a nice mixture of odd, extra-dimensional creatures along with suggestions about how they might provide dangers or opportunities for players. As an assistance to GMs, text also tends to include ideas about how these creatures might come up in a game, and brief ideas of planes of existence the players might be exposed to as a result.

The art was hit or miss for me. Sometimes it was evocative in a way I enjoyed. Other times it just struck me as kind of awkward.

Overall though, I found it a nice, satisfying supplement, a real font of ideas and suggestions, without being either overly exhaustive or too vague. I could wish more game material had this specific level of detail.

Awesome book! Adds a good way to really create a different character in DW! Clear and concise way of drawing them up and nothing seems like it would be game breaking but can still build some powerful characters if you really want to. Recommend for those looking for more to really dive in and customize characters and moves.

A wonderful recourse for mutations or strange magical effects of all kinds. One of my favorites and great inspiration for me.

Five stars for content and composition, one star for format. Landscape format is nonsense. Can't read the book properly, can't fit it on a shelf.

But the content is great, like everything JM does.

The game that saved me from spending years writing my own game that would have been this but clumsier and worse.

i have been gm for my group of friends for agood 5 years now and thisbook has been both great on the monsters andbuff that they all has gained or fought.

This book is a real mixed bag.

For players looking to get more of that D&D character creation style crunch, Class Warfare is a godsend. Dungeon World has beautifully simple PC archetypes, but from folks, they're too simple, and CW fills that gap perfectly.

For anyone else, the character creation process feels rather arcane and the book isn't well laid out (especially from a typography perspective).

Phenomenal ideas, relatively poor execution.

Unfortunately haven't been able to run dungeon world in some time but this had become my go to reference book for the most part (when ppl didn't want to play other homebrew options). Highly recommended!

At firrst, the biggest complaint I had about this amazing book was the artwork. But that was because I was expecting it to look like the art in The Nightmares Underneath and Nameless Grimoire, which wasn't fair. Now that I got over that gut reaction, I can say that I actually really like the art, it is whimsical, weird, and dangerous.

The exploration and hexcrawl rules are superb. They're easy to read and seem to be easy to implement.

The Monsters are as weird and dangerous as the art suggests. You won't see things like this anywhere else, which is a huge plus for me.

But the best part for me, a huge fan of TNU, is how much Johnstone Metzgar expanded that game. The amount of character options he hands to us is amazing, and each class is flavorful and interesting. (I really want to play a mutant goblin).

I gave the book 5-stars, with the understanding that at first I didn't care for the art but it won me over.

I like Dungeon Full of Monsters. I like megadungeons. The gist of it is, you have a mountain full of megadungeon goodness, and depending on where the characters enter, you end up in various levels composed of a group of maps which are random in their placement.

This is handy as the sections are each their own mini-dungeon with their own theme and such, and are very easy to prepare in a few minutes as the dungeons are often about 2-3 pages. My players and I are enjoying it.

I currently run this online and have one constant irritant with it though. The maps are stretched or otherwise not a regular grid. When you set the grid, the area you set will be fine...then you will notice how as the map progresses from that spot, your grid stops overlapping and you have map lines everywhere. On some maps, you will have multiple scaled grids on the same map portion ie regular squares then a secion of about 70% scale for one area of the map.

For theater of the mind style play, this is fine, but if you go through the trouble of making a book of PC maps, I'm not quite sure why you would stretch your maps and make the squares uneven.

A previous review suggested that the mechanics of the professions of The Nightmares Underneath were uninteresting, which utterly confounds me. In contrast, I find them to be a joy to play and run. They're quite well constructed, and employ elements of both OSR design and Powered by the Apocalypse design. Characters are fashioned to be hyper-competent at what they are meant to do, and yet the majority of them are simple enough to fit on one page of rules and description.

As an example, Thieves (which was mentioned negatively in that other review) will always find what is hidden if they spend a turn searching and are in an environment of their level or lower. If they search in a dungeon of higher level than they are, they will always be at least 2x as good as it as other characters, and if they quickly search an area in any environment (instead of taking a full turn), they search as other characters do (though they are still likely to be better at it, because of their probably-high Dexterity score). Additionally, they have four customizable options at L1 which give them Advantage on rolls related to being a Burglar, Con Artist, Mastermind, or Guild Thief, and they get +level bonuses to being stealthy, to initiative, and to rolls related to a majority of thief activities.

Fighters inflict bonus damage on physical attacks (as opposed to magical attacks) whether they hit or miss on their attack roll, get a bonus to low HP when they join a fight or press an attack, add their level to physical attacks and intimidation rolls, and choose between 5 martial styles that help to broadly define what type of fighter they are (uses retainers, high initiative, fights with a partner, wears heavy armor, fights unarmed).

These character archetypes are designed to do their thing well, to help focus and determine play. Other systems of the game provide additional color and background to the characters. For instance, I make heavy use of the random equipment package tables during character generation in my games, because they provide rich, unexpected color to the PCs. Ranging from the mundane ("you have a brand-new sword, a lantern and a flask of oil, a set of tools for the profession of your choice, and a recent personal tragedy that you are trying not to dwell on") to the fantastic ("you have a pistol that spits forth the concentrated fury of a dead age, long buried and forgotten; it never needs to be reloaded"), the equipment is evocative and begs for additional questions to be asked of the player, in the style of a Powered by the Apocalypse game. For the former result, taken from the table for characters of the Middle Classes, I want to hear more about why the sword is brand-new, and we can uncover more about the personal tragedy in play. For the latter result, which is what you get if you roll a '3' on 3d6 on the table for the Wretched and the Lost (the penniless, prisoners, untouchables) there's clearly a tale to be told on how the PC came by such an object. An entire campaign could be constructed around that character and object.

These are just a few examples of how masterfully and colorfully player characters are treated in this game. Dungeons are given new meaning and life by making them living incursions of nightmare that can pop up anywhere (the wilderness, a ship, that house over there), with an ecology that assists the GM with thematic dungeon design. Magic is democratized. Homebase villages/towns can be developed by players to confer specific mechanical benefits to the party. This is a brilliant masterpiece of a game, and it's free (though your hard-earned coin would be well spent on the gorgeous art-filled version).

Any gamer would be doing themselves a disservice to not pick this game up and play it at their table.

Treat this as a toolbox. Easy to convert to any d20 game, and many d6 games as well. Lots of great ideas for spells and spellcasters.

This Book has helped me create so many fun little Heroes, Monsters, and NPC's. If you are looking for a go-to to help build populace, consider this one of the best encyclopedias to have on your shelf. It takes a minute rolling out a creation but youll start to have a lot of fun when putting it together. Strongly consider using this to build first before you play. There are lots of tables and abilities that are too time consuming to read and put together on the fly during game time.

Wow. Haven't playtested, but design-wise, this is trippy and amazing!

While using random tables in role-playing games and war-games is a matter of preference, and not all games allow for random shifts of power, for those who use or allow them, this is a must-have book. Game Masters will have to put in some effort to establish rules for many of the mutations/powers presented due to the system agnostic nature of the book. Despite that, most of the mutations/powers are strange characteristics designed to offer more in the way of role-playing than raw game mechanics. For example, something like Backwards Body Parts would not require any special rules to cover it, compared to Sonic Blast which would be be treated as a form of attack. Even if a group has no interest in using random mutations and superpowers as part of character-creation, Game Masters would be surprise by the number of useful lists available. For example, the supernatural attributes, Demonic Phenomena, Taboo (also great for magic curses or acts of spiritual atonement) and Telltale, can be used to enhance the eeriness of horror or surreal settings. There are a ton of ideas buried within the text and tables to mine with this book. Most of all, GMs are not obligated to use the book "as is"; if the game rules you are using already feature similar content, the rules can override the book. Or, if you don't like certain descriptions, you can change them outright. You get a fair amount of page margin to write short notes, and you also get a few blank pages at the end to make longer notes.

While the original edition, as a file, is free and is good in its own right, the Revised edition is an all around better book due to all the added content and the better layout. The enhanced layout makes it like a dictionary when looking for desired content. For example, full-page black & white images are used to visually divide each section, appearing as thin black lines when the book is closed, along with edge index markers to show you what section you are on, which appear as thick black bars when the book is closed. Like a dictionary, the Mutation Descriptions section includes the category and alphabetical listing on the top margins of each page. As great as the indexing is, you will still find some entries really useful enough to add your own sticky tabs to them.

Buyers should also be mindful that the book contains a number of mutations of a sexually-related nature that would get really awkward when used carelessly around certain players.