it is widely believed that defense herpes have a silent 20% buff to their attack and defense stats. it is my understanding that data oriented forum members analyzed a lot of numbers and came up with this, just like they came up with an approximate damage formula.
I couldnt find any more info about this 20% buff. has SG actually confirmed it? denied it?
SG didn’t say anything about it.
You can see this on DoT heroes, for example:
Your Kelile have 800atk enemys Kelile have 800 attack too but her DoT is higher beacuse of the 20% (DoT is base on attack stat)
To best of my knowledge it was never officially confirmed by SG. Nonetheless, it seems to be working like it was analyzed from the numbers. 
thanks, guys!
20 thanks!