The increases are uneven all the way up. d4->d6 increases the average damage roll by 40%, d10->d12 is only an 18% increase, d12->d20 is a 62% increase.Rkhet said:Just seems wrong - everything increases by 2 from d4 to d12. Then it jumps by 8.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.