To be clear, I do not recommend doing this. It will slow the game down a bunch.
But, the math works, the results will be fair.
Okay so I thought of a way to reduce the expected roll to 1.333etc when trying to get a d4 result, but it’s not as straightforward to describe and complicates the process. OTOH it does also cap the rolls for that part to 2.
Basically:
If you roll 1-4, that’s the result, if not remember the result and roll again.
If the second roll isn’t 1-4, then compare first and second rolls:
5,5 = 1
5,6 = 2
6,5 = 3
6,6 = 4
Since 6^N always ends in 6, it can never be cleanly divisible by 5, so there is no way to guarantee a map.
I wondered about d7 whether that’s possible with d6 and guaranteeing number of rolls, because 7xN sometimes ends in 6, but I tested up to 5000d6 without luck. (2/2)
@Sophie I love how clever that is!
Still, the thought that you need to roll a bigger die twice to get a smaller die's result disturbed me, so I kept thinking:
What if we use the results on the sides of the die, instead of just the one at the top? That way, on a 5 or 6 top result, you look at the side that's facing you (push the die back with a straight object to disambiguate, if needed). The possibilities would be:
* On a 6: 2, 3, 4, 5 - treat 5 as a 1
* On a 5: 1, 3, 4, 6 - treat 6 as a 2
@Sophie To elaborate, coins side values of 0/4, 0/2, 1/2 will give a d8 (basically just binary bit encoding without allowing a 0 in the smallest bit because dice don’t usually have zeroes)
I wonder if anyone’s made an rpg that uses only coins and uses their denominations, like flip some coins and add up the monetary value of all the face up ones
Attached: 1 image Oh I forgot to include these in the pic, a d1024 (ten binary dice)
@Sophie my vintage copy of "What Is Dungeons and Dragons" had a very similar method.
https://www.goodreads.com/book/show/2271678.What_is_Dungeons_and_Dragons_
@Sophie If you want to use a D6 as a D6, you can consult my patented random diceroll table over here: https://meow.social/@Owlor/113981667963711204 (a shitpost I made as a really stupid joke)
I'm gonna bookmark this post as reference cus I'm always on the lookout for ways to stretch using only a couple of D6es to its limit (these days polyhedral dice or dice rollers aren't that hard to come by, but as a nod to both japanese and indie TTRPG tradition I like to use D6es only as much as possible so my games are playable by just raiding an average board game shelf).
Content warning: not screenreader friendly
@dx okay so I got nerd-sniped anyway lol, and your orientation thought is the best I can do. A d6 can be a d5 by:
1-5 is top face: job done
6 is top face: the 2 face is on the side, measure the angle it points, it’ll fall somewhere in a fifth lol
(If you measure a side face’s direction then even pipped dice are fine)
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