OD&D Supplement II: Blackmoor (1975): Dave Arneson’s Other Dungeons & Dragons

 

When Dungeons & Dragons appeared in 1974, it was already the product of more than one campaign, more than one imagination and more than one approach to fantasy gaming.

In our look at Greyhawk, we saw how Gary Gygax's campaign helped push the new game beyond the foundations established by the three little brown books. Now it is time to look at the other great campaign at the heart of the game's creation.

Blackmoor was Dave Arneson's campaign, and Dungeons & Dragons Supplement II: Blackmoor, published by TSR in 1975, was the first substantial attempt to bring some of Arneson's ideas into the published game.

It is an unusual book. Despite its title, it is not really a campaign setting guide. Instead, it is a collection of rules, monsters, treasures, experimental systems and, most importantly, The Temple of the Frog — one of the most historically significant adventures ever published for a role-playing game.

The Other Half of Dungeons & Dragons

The history of Dungeons & Dragons is often reduced to the story of Gary Gygax and Dave Arneson. That is understandable: the two men are the game's credited co-authors, and their work became the foundation of the hobby.

But neither man developed the game in isolation.

Arneson's Blackmoor campaign was already experimenting with ideas that would become central to role-playing games before the publication of Dungeons & Dragons. Players controlled individual characters rather than armies. They explored dangerous environments under the direction of a referee. Characters survived from adventure to adventure, gaining experience and developing their own histories.

These ideas were part of a wider culture of experimentation among early wargamers. Campaigns developed their own rules, players shared ideas and referees continually changed their games in response to what happened around the table.

Dungeons & Dragons therefore did not emerge as a finished design. It was the beginning of an ongoing process.

Dave Arneson's Blackmoor

Arneson's Blackmoor campaign was one of the earliest environments in which this new style of play was explored at length. It had its own characters, locations, monsters, factions and adventures, but its importance goes beyond the setting itself.

Blackmoor represented a way of playing fantasy games in which the referee and players were jointly creating an ongoing story. The rules were tools rather than an end in themselves, and the campaign could develop in directions that its creators had not originally anticipated.

When TSR began publishing supplements to the original Dungeons & Dragons rules, the decision was made to publish material from the two campaigns most closely associated with the game's development.

Gygax's material became Supplement I: Greyhawk.

Arneson's material became Supplement II: Blackmoor.

Supplement II: Blackmoor

Blackmoor was published by TSR in 1975 as the second supplement to the original Dungeons & Dragons rules. It was written by Dave Arneson, edited by Tim Kask and illustrated by David C. Sutherland III, Mike Bell and Tracy Lesch.

The book followed the basic structure of the original D&D rules, with material dealing with characters and magic, monsters and treasures, and adventures in the underworld and wilderness.

But it was very different in character from Greyhawk.

Where Greyhawk helped refine and expand many of the conventions of fantasy adventure gaming, Blackmoor often feels like a collection of experiments. Some of its ideas would become familiar parts of later role-playing games. Others would remain curiosities of early D&D.

That makes the supplement an unusually valuable historical document. It captures a period when nobody yet knew exactly what a fantasy role-playing game was supposed to be.

The Monk

One of the most striking additions was the Monk.

The original D&D rules had three basic character classes: Fighting-Man, Magic-User and Cleric. Greyhawk had already demonstrated how much the game could be changed by adding the Thief and the Paladin.

Blackmoor went in a very different direction.

The Monk was an unconventional martial character whose abilities went far beyond those of an ordinary Fighting-Man. It was an early example of D&D reaching outside the straightforward medieval fantasy archetypes that had inspired its original rules.

The class also demonstrates just how experimental early D&D could be. The boundaries between fantasy literature, popular culture and the ideas being invented at the gaming table were still extremely fluid.

The Assassin

Blackmoor also introduced the Assassin as a character class.

Again, this was a considerable departure from the simple three-class structure of the original game. The Assassin represented another attempt to create a specialist character whose abilities and role were defined by something other than simply being a better Fighting-Man.

These classes would not necessarily become permanent fixtures of every later version of D&D, but their presence is historically important. They show players and designers experimenting with what a character class could actually represent.

Rules for a Stranger World

Some of the most interesting material in Blackmoor has nothing to do with character classes.

The supplement contains rules for underwater adventures and combat, along with a hit-location system, diseases and other unusual situations.

This is another indication of the experimental nature of early D&D.

The original game had provided a framework for dungeon exploration, but players were already asking what happened when an adventure moved beyond the familiar dungeon environment. What happens when characters fight underwater? What happens when a particular part of the body is struck? What happens when disease becomes part of an adventure?

Blackmoor did not necessarily provide the final answers. Instead, it showed that these questions could be incorporated into the game at all.

The Temple of the Frog

Then there is The Temple of the Frog.

Among everything in Blackmoor, this is perhaps the most important piece of material from the perspective of the history of role-playing games.

The scenario was derived from Arneson's Blackmoor campaign and presented players with an actual adventure location rather than simply instructions for creating their own adventures. It occupies a substantial portion of the supplement and provides a glimpse of the sort of strange, dangerous and unconventional scenarios that could emerge from an established campaign.

Its historical importance is difficult to overstate.

The original Dungeons & Dragons books taught referees how to create adventures and gave them the tools with which to build their own worlds. The Temple of the Frog went a step further: TSR was now publishing an adventure that other groups could actually play.

It is generally regarded as the first published role-playing game adventure scenario, making Blackmoor an important milestone in the development of the adventure-module industry that would eventually become one of the defining features of tabletop role-playing games.

A Book Built by a Community

It is also important not to treat Blackmoor as the work of Dave Arneson alone.

The title page credits Arneson as the author, but also records his thanks to Gary Gygax, Tim Kask, Rob Kuntz and Steve Marsh for suggestions and ideas. Tim Kask edited the book, while Sutherland, Bell and Lesch provided its illustrations.

The surviving history of the manuscript also illustrates how rough and experimental the material could be. Kask later recalled that the original submission was a large collection of handwritten material containing charts, tables, maps and duplicated information, requiring substantial editorial work before it could become a publishable book.

That is revealing because it takes us back to one of the central truths about early Dungeons & Dragons.

The game was being built by a community.

Arneson had his campaign. Gygax had his. Their players contributed ideas. Other gaming groups developed their own rules. TSR's magazines would soon provide another way for those ideas to circulate. Some innovations became official rules; others remained house rules or curiosities.

The published game was therefore not simply a series of inventions handed down by a single designer. It was a record of ideas being tried, changed, shared and eventually printed.

Gygax and Arneson — Still Working Together

Today it is easy to read the history of Blackmoor with the later dispute between Arneson and Gygax already in mind.

But that is not how the book appeared in 1975.

At the time, Gygax and Arneson were still being presented as collaborators and co-authors of Dungeons & Dragons. Indeed, Gygax wrote the foreword to Blackmoor, and the tone of that foreword is striking.

Rather than minimising Arneson's contribution, Gygax praised him as an innovator of the dungeon-adventure concept and described him as an exceptional Dungeon Master. Gygax even wrote that, despite having co-authored the original game and having spent hundreds of hours playing and creating Dungeons & Dragons, he would rather play in Arneson's campaign than any other.

Read with the benefit of hindsight, those words carry an additional weight. The relationship between the two men would later become deeply strained, eventually leading to a legal dispute over royalties and the rights surrounding Dungeons & Dragons.

But that conflict belongs to a later chapter.

Blackmoor belongs to the period when the two creators were still contributing to the same developing game.

What Blackmoor Really Was

Despite its title, Blackmoor is not the comprehensive campaign setting book that a modern reader might expect.

There is relatively little description of the Blackmoor world itself. The supplement is much more concerned with rules, monsters, treasures and adventures than with providing a gazetteer of Arneson's campaign.

For a fuller look at the Blackmoor campaign itself, readers would have to wait for The First Fantasy Campaign, published by Judges Guild in 1977.

That distinction is important.

Supplement II: Blackmoor is best understood not as “the Blackmoor setting book”, but as Dave Arneson's contribution to the rapidly expanding rules and adventure culture of early D&D.

The Other Path D&D Could Have Taken

That may ultimately be the most interesting thing about the supplement.

Greyhawk showed one direction in which D&D could develop: more character options, more monsters, more magic and increasingly detailed rules for fantasy adventuring.

Blackmoor showed another.

Here was a game willing to experiment with unusual character concepts, underwater adventures, diseases, hit locations and strange scenarios. It was less concerned with defining a finished system than with asking what else could be done with the new form of game that Arneson and his contemporaries had helped create.

And at its centre was The Temple of the Frog, an early glimpse of a future in which adventures themselves would become published products.

Blackmoor therefore occupies a unique place in the history of Dungeons & Dragons. It is not simply the second supplement. It is one of the clearest surviving records of the experimental, collaborative culture from which the role-playing hobby emerged.

Legacy

By the time Blackmoor appeared in 1975, Dungeons & Dragons was already changing faster than its original creators could have anticipated.

The game had begun with three little brown books and a radically new idea: that players could take on individual characters and explore a world controlled by a referee.

Greyhawk expanded those foundations.

Blackmoor pushed them in new directions.

And beyond both books, players across the growing D&D community were continuing to invent, adapt and share their own ideas.

That process would define the history of the game for decades to come.

Dave Arneson's Blackmoor was not the whole of D&D. Neither was Gary Gygax's Greyhawk. Together, however, they reveal something essential about the game's origins: D&D was never created in a vacuum. It was created through play.

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Collector's Note: Blackmoor appeared in numerous printings with differences in printing information and other production details. If you're trying to identify your copy, see my companion article Collector's Guide to Dungeons & Dragons Supplement II: Blackmoor.