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ive3wusq7's avatar

"D66 tables can be hard to explain"

Isn't it mostly a naming issue? (since there is no "D66" in the same sense as there are "D12s" or "D100s" *)

If we just call them "tables" and explain "roll one six-sided dice for the column, another for the row", there isn't much room for confusion, no?

* Well, except with a sleigh of hand, switching from base-10 to base-6, which is indeed confusing for non-math-people ...

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Jeremy's avatar

The other downside is it interacts poorly with the free choice of faces digital dice enable, where you really could just roll a d66 in a jiffy. I’ve occasionally seen the tables described as d36 but numbered for easy selection using 2 d6 as a way to not further confuse dice notation.

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Exeunt Press's avatar

Yet another reason to not call it a D66 in the rules and instead just explain what you want to accomplish and how to do it. :)

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Exeunt Press's avatar

I think you bring up an important point. Dropping the D66 nomenclature doesn’t lose anything (who cares what it’s called?) and makes it easier to explain.

(Thinking about it, games like Scout don’t use the technical terms “card shedding” or “ladder climbing” in the rules. They just explain what to do.)

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Jeremy's avatar

In case you haven’t run into it, anydice.com is fantastic for quickly seeing the distribution, or even cumulative probability, of different dice combos. The cumulative readout is really handy for roll-under systems; it can also cumulate the other way (% rolled above N) to simplify analyzing roll-over systems without getting clever with the custom programming language it supports.

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Exeunt Press's avatar

Anydice is great, and recommended. For this one I thought it would be fun to just run 4000 random numbers in Excel and chart it just so it shows the rougher edges. In other articles I've used Python + Seaborn to do charts, including some KDE plots that are always pretty. :)

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Alex White's avatar

Another thought - it is perfectly possible to have 1-12 results or even 1-18 results smoothly with 2d6, using the old fashioned approach where the first dice is 1-6, and if the second dice is 1-3 leave as-is, if the second dice is 4-6 then add 6.

Same for 1-18 results; leaving the first dice as-is when the second dice is 1-2, adding 6 for 3-4 and adding 12 for 5-6

This is orthogonal to the main point of your article, the d66 mechanism, but I thought it was worth mentioning.

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Exeunt Press's avatar

Hrm… not sure I understand this approach.

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Alex White's avatar

If I write it out longhand it’s going to look complicated, but perhaps a modified version will make it clearer what I’m talking about. For the 1-12 result, I’m going to use even and odd on one of the dice for the purposes of the illustration (1-3 is easier in practice IMO)

Die 1 | Die 2 | Result

- - - | - - - | - - -

Odd | 1 | 1

Odd | 2 | 2

Odd | 3 | 3

Odd | 4 | 4

Odd | 5 | 5

Odd | 6| 6

Even | 1 | 7

Even | 2 | 8

Even | 3 | 9

Even | 4 | 10

Even | 5 | 11

Even | 6 | 12

Does that make sense?

In the early days of D&D no polyhedron was labelled 1-20, so we always rolled a twenty sided d10 and a d6 together. If the d6 was 1-3 we read the d10 as it was, if it was a 4-6 we added 10 to get the numbers 11-20. Later on we painted half the faces on the twenty sided d10 so we could get it in one roll!

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Exeunt Press's avatar

Now I get it! That’s really interesting. Thank you!

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Jeremy's avatar

I think the description is complicated by using one of the d6 as a d2 or d3. That die is effectively acting as a range/offset selector for the other die.

Similarly, early d20s were marked 1-10 twice over and you’d need to designate the “high half” by dotting or coloring the faces differently. So it was a d10 plus a d2 for hi/lo basically in one die.

As a dice expression, it’s basically like 6*(d3 - 1) + d6 to get a d18. And then you can use ceil(d6/2) to get a d3 out of a d6.

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Ben Hoban's avatar

Oh shit I just read that and realized I came off like a bot…

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Ben Hoban's avatar

Not yet

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Exeunt Press's avatar

It’s good to have goals for the new year!

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Ben Hoban's avatar

Wow, these posts are next level. So impressed with the level of commitment to great content.

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Exeunt Press's avatar

Thank you!

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GMaia's avatar

Howdy, very interesting however if you want to have a quality leap on this topic, here's my reccomendation: there is a great guy, Torben Mogensen, who is really an expert on dice mechanics! He wrote a white paper years ago, I have the 2006 version, but at this link there is a more updated version of 2016: http://hjemmesider.diku.dk/~torbenm/Troll/RPGdice.pdf

I honestly do not remember how I tracked this document but that is definitely worth a read... and in addition Torben is an extremely kind and available fellow: if you write him, he will for sure send you feebacks (very educated let me add!). Hope it helps, ciaooo

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Exeunt Press's avatar

I love academic (or academic-style) papers on tabletop board games and roleplaying games! Will check that one out. Thank you!

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GMaia's avatar

Happy you find it interesting, pls consider that you can reach the author: he's a very kind and open guy!

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Philip Blyth's avatar

Another thing I love about these dice matrix tables — especially for solo play — is that if the result for 23 doesn’t spark inspiration, you can guiltlessly choose the result for 32 instead 😅!

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Exeunt Press's avatar

Hah! So true! I should have mentioned that in the article.

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Jeff Pettiross's avatar

Fiasco (by Jason Morningstar/Bully Pulpit Games) has an implementation of D66 that I like. It combines the variety with a drafting mechanic. Here's an example of one of the D66 tables from a playset (think module or setting) that revolves around a dramatic group of dramatists.

https://www.dropbox.com/scl/fi/8exxvbv9r3c32630te2qt/Fiasco-playset-D66-example.png?rlkey=ds3jo8mokned580921ls0jm19&st=a9q7sbec&dl=0

As part of the setup for this GM-less one-shot game, you roll a big pile of d6s, four for each player. Players draft a die at a time from the pool to add information about Relationships, Needs, and Locations they share with the two players physically next to them at the table. The first die they draft names the category, the second picks the specific instance.

So, for example, a player could pull a 4 from the pool and announce they are using it to establish a Romance Relationship with the player to their left. A subsequent draft of a 1 could further specify that Relationship as a Showmance.

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Exeunt Press's avatar

That's really interesting! I've actually never played or read Fiasco, even though I've heard about it countless time. Perhaps I should check it out.

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Jeff Pettiross's avatar

Totally worth it IMHO to try at least once, both as a work of game design and for the collaborative storytelling it enables. Each playset is simply three D66 tables, but their writing quickly evokes a world for both novice and experienced storytellers (a term I'm using in the most general sense, not specific to this game).

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darius/dare carrasquillo's avatar

I love this stuff but what i really want are blank templates so that gamers can create setting specific tables that are populated via play and other tables.

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Exeunt Press's avatar

Templates are always helpful! There might be some on itch.io.

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Alex White's avatar

I first came across d66 tables in an early 1st edition traveller book! I want to think it was connected with 76 patrons in 1980 but can’t be sure after all this time! Not so surprising when traveller was probably the first of the big games to aggressively restrict itself to only using D6s

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Exeunt Press's avatar

I do like to try to use only d6 when designing games where the player needs to “bring their own dice.” I’ve been surprised at how many people who are interested in EP solo games don’t own a set of polyhedral dice (based on conversations at conventions).

If I were selling 5e supplements, using different non-d6 dice wouldn’t be an issue! ☺️

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Alex White's avatar

Aha, a bit of research later, and it was actually in the original traveller core rules in 1977!

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