d8s with duplicate sides gang
Flipping a coin two times and reading the result as binary gang. (Don’t actually do this, coins aren’t as fair)
They’re only off by about 1% and the bias depends on which side was up, it’s not that bad. I wouldn’t expect most inexpensive dice to be substantially fairer than that.
Honestly I’m sure this is the best solution. I get that a d4 is the obvious choice for something that should have a 1/4 chance of happening but a d8 with 4 numbers twice would be the most appropriate.
The only downside I can see is that a d8 and a d8/4 would be easy to mix up at first glance.
You don’t even need a special die for this. Just roll a d8 and subtract 4 if it’s 5-8. Just like using a d6 as a d3.
Honestly you only need a d20 and a d6. D4? Divide by 5. D8? D20/5 x d20/10. D12? D6xd10/2
MATH BABY
D8? D20/5 x d20/10
Am I missing something here? Can this even generate 5 or 7?
D20/5 gives [1…4] and D20/10 [1…2], of course assuming whole numbers. Where to get the factors for 5? 5 can be factored only as 5x1 or 1x5 and the 5 cannot be found either in d20/5 or d20/10. Same is true for 7.
And I don’t see it happening either if we allow rational numbers. To get 5 we would get the following expressions
5= d120/5 x d220/10 = d120 x d220/50
or
250= d120 x d220
And two d20 multiplied together cannot give us 250.
Math baby?
To keep the same probabilities, you can only reduce and only to one that is a factor. E.g. d20 can be equivalent to d10, d5, d4 and d2.
Multiplying the rolls messes things up. As an example, for d12 as a d6xd2 you have double the chance to roll 2, 4, and 6 and no chance to roll 7, 9, and 11.
You could make the equation a little more complicated (6×(d2-1))+d6 to make it work.
You already have d10 and d100 (d00? What do we call the other one?), so there’s precedent for duplicating shapes.
I’d actually like to see a d8/d4 hybrid. Basically take a caltrop d4, snip a bit off the ends to make a truncated tetrahedron. You’ll then have 4 large hexagonal faces and 4 small triangular ones. Put the numbers on the triangles. If it lands upside down, then it is just house rules whether to use the bottom face or to reroll. Or just number the large faces too.
It’s a similar concept to the round safety d4s; just less… round.
Like this?
https://www.kickstarter.com/projects/263612668/rollable-4-sided-dice
They’re out there somewhere…
Just use a dreidel, ya dingus.
For your health.
I don’t get what this means, roll on top or bottom of what?
There are 2 kinds of D4 dice. The result can be on the bottom or on the top of the “piramid”.
GURPS for the win, bell curves are the way to go.
Arch d4 gang
