Alright, sorry for the late respons, and thankyou for all the info, im gonna go delve for that armor calculator. I can use that in-conjunction with Increase spell dmg taken ability and it will get the right effect.
And yes, i meant changing the percent amount of how much damage is being taken in by a particular unit.
Edit: Found the damage calculator, and then scrapped that idea lol. Found a damage detection script and implented that, works fantastic. Thanks for the insight guys.