Nice job, Zelc. I had a messier version for crunching numbers, but am going to start using yours.

I am confused about the purpose of sumproduct function in the [to hit] and [to dmg] final numbers, though.

It seems to be throwing off the [to dmg.] For example with attacker numbers 5/6 and defender numbers 2/3 I get 3's and 4's.