1. Go to Helper.cns
2. Head down and click statedef 3959.
3. Press CTRL+F and type in palfx then search.
4. Change any of the values of "add" using RGB color codes and when the number is greater than 1 add var(18) into "mul". (Refer to image 1.)
5. Do that again in State 9883. 

If you want to change the size of the aura, you need to find the varset located at the bottom of the statedef. This need to match with
the character size otherwise they will look off. (Refer to image 2.) You also need to change statedef 3950 aura if you want the charge attack
Aura to match.