OK.
I'm no statistician, but I like challenges.
Here's a further modified worksheet. I won't claim I did it 100% correct, but it should be reasonable.
It calculates for 1 reroll of a single black shield.
It also assumes you choose to reroll the BS on the die with the best odds of giving you a Skull (or White Shield for the defense section) if rolling multiple types with varying probabilities.
It keeps expected damage constant and adjusts the likelihood of that damage to make it easy to compare the effect of the potential reroll.







