Hai!
I had an idea of getting Runes which had Might Duration, and after looking at a number of them, I saw that both “Strength” and “Hoelbrak” Runes have +25 Power, then +20% Might Duration.
My Question is do the two 20% Might Duration work together, so it should last much longer? Or does it only count one for the time being. Because I also saw under the Rune “Water”, at rank 2 it has +15 Boon Duration.
So if I had 2 Strength, 2 Hoelbrak, and 2 Water Runes, would that equal +40% Might Duration and +15% Boon Duration?
If you know, pls do tell 
. Thank you!