The Mystery of Dave Arneson's Engine

(This article was written as part of Murkhill's Week-long celebration of Dave Arneson. Click the link to find more great articles!)

Like many other Dungeon Masters, I had never heard of Dave Arneson until well after his death. He had been edited out of the history of the game, but what we know as Dungeons & Dragons is based on the game of Dave Arneson’s invention. You see, Dave Arneson did not just develop a game, the key word here is that he INVENTED a game. This is something that hasn’t been done in our common age. Folks who designed games always based the principals from ancient games and they put a new spin on them, but Dave didn’t do that. The very idea of playing a game without a board or markers, to our knowledge, has never been done before.

The game which he invented doesn’t have a name, so we refer to it as Blackmoor, and it is an elusive concept. There are different forms of it; there were the games that Dave ran at conventions or private games with strangers who wanted to delve into the mysterious dungeon, but at this point, the actual game of Blackmoor had not been played in many years. The earliest games were more along the lines of what we’d expect from a long-term D&D group, and the world that they discovered and developed through play is what we now know as Blackmoor.

Now, what made Blackmoor so revolutionary was how it was played. Players could try anything, and they were expected too! Arneson developed systems on the spot to determine the results of each action, and he did this in real time. He didn’t have a book which told him the rules, he invented rules at the table which he felt would give the best results.

It is said that Dave based his game on TSR’s Chainmail, and he did use it briefly, but as his book “The First Fantasy Campaign” will show you, he quickly abandoned Chainmail in favour of his own knowledge that he had gleaned from his years as a wargamer.

The actual campaign of Blackmoor was much more advanced than what would become Dungeons & Dragons, on some levels it was a cooperative game, but on others, it was very competitive; and there were different levels of play. Blackmoor was both a strategic game and, separately, a tactical game. Players controlled armies at what we would consider low levels of play, and sometimes these player-controlled strongholds appeared to act as villains. We know that Arneson did use miniatures from time to time, could this be what was going on? Just a test of a player’s defences?

This is something that I myself have discovered about the game; one can use it as the basis and setting for a huge variety of games, be it tactical miniature play, free-form exploration, or even a well-developed mystery which incorporates everything on an as-needed basis. One can play an individual or even a nation’s decision maker! The limits are truly up to our ability to imagine.

The original players were well versed in wargames, so their games reflected this background, but that doesn’t mean that the game was one dimensional, as it wasn’t. It didn’t become one dimensional until the public became interested, then Dave would take this game, in its preserved state, to them. In this game, players rolled up a character and Dave would take them into the dungeon; but was this game Dungeons & Dragons? The answer is no.


At its heart, this was a very simple game of logistics. The idea was to go into the gilded hole and return with enough money to perhaps finance another expedition. Sounds like D&D! However most players didn’t get a second expedition as it was a one time only kind of deal, but for the Blackmoor bunch, they did get more than one shot at it, and this aspect of the game literally distracted them from the original campaign. They were building a system as they went, and like I said, the game required set rules that never changed and another set of guidelines to allow the DM to handle every situation. This was the game that Gary Gygax played, the game that Dungeons & Dragons was based on. Finding this game is a challenge all in itself, elements are hidden inside of D&D but D&D was ultimately a corporate product while the game of Blackmoor was not. I would like to share with you some of my thoughts on how I feel the game of Blackmoor differed from Dungeons & Dragons.

1.       The Magic System

The spells cast by Wizards and Clerics were purchased beforehand. Spell-casters were limited by their actual spell level, but one was only limited to the spells which one managed to purchase and was able to carry with them. This system required strategy on the players part, choosing which spells to bring with them and forced logistical decisions, as the spells themselves took up what the character could carry out, which was treasure.

2.       Equipment

Everyone had to be smart about what they brought down with them. How much a character could carry was strictly observed. This was on purpose and while it has its place in D&D it often isn’t observed. Arneson was a master of relieving the players of their gold, having to abandon equipment and placing limitations on how much one could bring back kept the game going. Not to mention the players having to figure out ways to keep the treasure that they did have safe.

3.       Armour

One of the contentions between Arneson and Gygax was the combat system. It is my belief that, like the wizard, the fighter had to plan his trips as well. This required purchasing and repairing armour which took damage so that the character's body did not. Gygax used an avoidance mechanic, while Arneson didn’t. If one had Plate mail, one had to deal with the weight of the plate, but the armour would take X amount of hits until it was ruined and the character was exposed and took the damage himself.

4.       Hit Dice

I personally wonder if hp were Gygax’s addition to the game? I am not sure if Arneson used them. I believe that a character could take 1 hit per level before death. I could be wrong, each HD could = 1d6 of hit points, but during my games, I tend to abandon hit points in favour of the HD method, but I do go back and forth depending on the exact situation and the context of the battle.

We also don’t know how much of an influence Chainmail ultimately had on Blackmoor, if a Monster had 4HD did the players need to hit him 4 times in the same round before it was dead? It is doubtful since each successful hit reduces the armour's ability to protect you, but Arneson was always changing things up, and he did play with hp at D&D conventions and while he had no qualms about killing temporary characters, the Blackmoor bunch didn’t seem to have a very high mortality rate. This could be due to player skill or due to design as Arneson never stopped play-testing.

5.       Dice

Arneson’s system did not use the D&D dice, as they were not really a thing that one could buy yet. Instead, he relied on d6s to generate statistical odds. He was a big fan of percentages, how he decided each roll is still kind of a mystery to me. Many wargames still rely only on the d6, and no doubt the study of these systems hold the answers.

There is much more to the enigma of Blackmoor, it wasn’t just a combat/exploration game, but a game that simulated a person who had to prepare for things. It was the ultimate wargame campaign that put the player in charge of all of the things that standard wargames took for granted and was presented in a way that required the imagination of the participants to envision what their characters were seeing. This game blended every conceivable element, but you can see a specific focus on logistics, a reliance on the player's ability to prepare and interact with the setting, and also cemented the idea of dangerous combat that was best avoided if at all possible. The focus of the game wasn’t necessarily becoming god-like beings, it was a game that allowed the players to feel and explore both the setting and their character. The sad thing is that Arneson’s engine doesn’t have to be limited in any way, it can simulate any time and any situation. There is still more work to be done on the engine, but this work has stopped with Dungeons & Dragons which immediately put limitations upon it.


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