Converting Ratio Charts



Has anyone every attempted to convert or “update” ratio charts you find in older games? I am not as familiar with this style and would love to try and change it to dice rolls or something a bit more understandable at a glance. I know it’s just a bit of quick math and wouldn’t take long too long to learn but I am still curious if there is a more “modern” way this can be done.

I have “The Creature that Ate Sheboygan” chart as an example.

As always, thanks in advance,


Are you wanting to convert it to ICRPG?


Yes, but being honest I’m not sure if it’s just too much of a different system to even make it possible. I’ve seen these types of ratio charts in other rpg’s so I’d like to be able to covert them to use those modules.


Hmm… I’ll chew on it and get back with you.

My general philosophy when converting is to try and capture the essence of the source rather than a perfect one to one. I think it would also depend on how these charts played into the game itself.


That makes sense. I just would like to try and drop the steps down a bit. So in this one 2-1 odds give us a 50% chance to destroy a building, so for this it’s as easy as choosing odds or evens or possibly have both players roll 1d6 and the higher score wins. But beyond that I start to get muddled down in the math. I thought about the more of an advantage you have the higher dice you’d roll (still with highest number winning) so 1d4 v 1d8; the d8 has a much better chance to roll higher but could still lose to a d4. I just don’t know if the scaling of odds works out well or not


To add to this, I know I could easily take story elements and get the jist of how it’s meant to “feel” and use ICRPG rules.That said if I come across some sort of chart like roaming monsters that relies on the odds working the way they are intended to I would hope to find an easier way to quickly roll and, statistically, get the same result. I wouldn’t want monsters showing up more or less than they were intended to.