Thanks to KJDavies for the link in his weekly roundup. Specifically, he linked to my mechanic for using roll under d20 + d10 for a skill check.
Here is a graph for your consideration:
I graphed the three mechanics mentioned in the post. Basically it shows that results above 21 begin to show diminishing returns. In other words, once a character achieves a score of 25, the benefit of pushing on to 30 is not so large an advantage.
One thing I haven't done yet is to look at this mechanic's effect on combat. Maybe it is tradition for me that I don't want to go into that direction. I'd like to say something at the beginning of Andras to the effect of this:
d4, d6, d8 and d10 are used for damage
d12 is used for initiative and surprise
d20 is used for combat
d20+d10 are used for non-weapon proficiency or special abilities. (Use a d30 if you prefer linear probabilities.)
Believe me when I tell you that if I could incorporate a d24, I would. 🙂
Next up, a crystal magic wielding rival for the Fire Primordials on their own plane and a look at the Water Primordials.