2d6 – the original tabletop role playing dice mechanic

Is 2d6 a hype? I see it everywhere. It’s in games Powered by the Apocalypse like Dungeon World, it’s in Maze Rats and Stars without Number.

Powered by the Apocalypse games introduce three possible outcomes to a roll of 2d6:

10 or more: you succeed

7 to 9: you succeed, but there’s a problem

6 or less: the game master gets to make a move, probably introducing even more complication.

That’s cool, it drives the story forward.

The B/X edition of Dungeons & Dragons (1981), which has become sort of lingua franca in the OSR scene, has morale and reaction rolls based on 2d6. In the lack of persuasion skill rolls like deception, fast-talk or savoir-faire, reaction rolls are an important, and actually quite universal mechanic to adjucate non-combat encounters. It goes like this:

2d6monster reactionretainer reaction
2 or lessimmediate attackoffer refused;
reaction -1 on the next roll
3 – 5hostile, possible attackoffer refused
6 – 8uncertain, monster confusedroll again
9 – 11no attack, monster leaves
or considers offers
offer accepted
12 or moreenthusiastic friendshipoffer accepted; morale +1

Quite a lot of role playing opportunity stuffed into this table. Especially the 6 – 8 range should prompt for some interesting social interaction. Of course the GM can liberally count in charisma modifiers and bonus points for good role playing, bribes offered, or penalties because of overall bad behaviour.

Then 2d6 is the principal die roll in many iterations of the Traveller rules up to Mongoose Traveller and Traveller 5. Classic Traveller was released in 1977. And by the way, there is also the Cepheus Engine, an OGL’ed science fiction system based on Mongoose Traveller 1st edition. There are many supplements for Cepheus, also for non-sci-fi genres, turning it into something like generic universal 2d6 based role playing game system.

But it goes further back. Just look at Chainmail, D&Ds supposed predecessor, published in 1971. The man-to-man combat table uses 2d6 against armor class, just like Classic Traveller.

Blackmoor obviously was the first ever tabletop role playing fantasy campaign. Some time ago, I discovered a post on the gaming experience in Blackmoor. Guess what kind of die rolls were done most of the time? Some character sheets from the Blackmoor campaign have been preserved. Isn’t it suggestive, that attributes and skills had numbers mostly in the range of 2 – 12? The Secrets of Blackmoor documentary released recently is well worth a look if you’re interested in the history of geek culture.

Now I find this quite intriguing. Most people think of a d20 when it comes to role playing and iconic images of dice, but rather likely the original role playing dice were 2d6. In one of my recent posts on reddit I asked how the Classic Traveller rules might be related to the Blackmoor campaign. An interesting discussion ensued and of course the answer is obvious. The designers of Blackmoor, Chainmail, D&D and Traveller knew each other, probably exchanged ideas on game mechanics, 2d6 was commonly used in war games, even before Blackmoor, and after all, d6s were much easier to get at then those funky dice D&D demanded.

Just as a reminder, 2d6 result in a simple bell curve (well, more of a roof top curve actually). Here are the odds:

2d6absoluteat least
22.78 %100 %
35.56 %97.22 %
48.33 %91.67 %
511.11 %83.33 %
613.89 %72.22 %
716.67 %58.33 %
813.89 %41.67 %
911.11 %27.78 %
108.33 %16.67 %
115.56 %8.33 %
122.78 %2.78 %

Finally let my cite this awesome catch all 2d6 based roll playing mechanic found on Norbert G. Matauschs blog, the post is called Back to really simple role playing:

we both roll 2d6; if I’m higher, I say what happens, if you’re higher, you say what happens; if we’re close, we negotiate

What more do you need?

Rules for traveling and hanging around

Here are some house rule for open table fantasy sandbox games.

Hanging around at the tavern

Player characters who don’t take part in an adventure, because their players couldn’t make it to the session, are supposed to hang around at the local tavern. It costs them 1 gp per day to stay there. This may well lead to going into depts, but that’s their problem.

Traveling

Player characters who need to travel quickly in order to catch up with a party may travel 18 to 90 miles or 3 to 15 hex per week. It costs them 15 gp for a week of traveling. Roll on the following table for each week traveling (i.e. if you need to travel 16 hexes, you need two weeks, so roll twice!). You gain the number cast on 2d6 times 20 XP per week!

2d6 event
2 you disappear and become a non-player character. Only the GM knows what happend. You might be found and become a player character again if the party successfully finds you.
3 Something bad happens. You’re traumatised and lose one level.
4 you’ve been assaulted and robbed. You reach your destination with nothing but rags (AC 9) and a cudgel (1d4).
5 you get injured and lose one week of traveling time – roll again.
6 you get help from some higher npc – you owe him a favour now.
7 you make an interesting discovery. You couldn’t gather much, but you’ve found (1) the entry to an unknown cave system, (2) ancient ruins, (3) the lair of a terrible monster, (4) a gate to another world.
8 you meet a traveling companion, roll again with +2. You get +2 on a reaction roll, if you want to hire him as a retainer.
9 you find some work on the way, and earn 3d10 gp
10 somehow you come in possession of a treasure map
11 you find a valuable gem (1d10*100 gp), lucky you
12 you find a magic item (GMs choice)

9 to 5 jobs for adventurers

Characters who stay at some place for a longer period of time might try to find work. Roll 2d6 plus charisma modifier. On a result of 8+ you find a job and earn 2d4 * 10 gp per week. If you miss you have to wait for a week and earn nothing. On a critival miss (2 on 2d6) wait two weeks before roling again.