Mironko

Hi I would like to add condition to mammonite skill, when you will have discount on lvl 10 then your mammonite skill will be for free, and each level of discount will be cheaper...(for example . Discount lvl 1 - Mammonite lvl 10 costs 900, Discount lvl 2 - Mammonite lvl 10 costs 800 and etc ). How can I do this please? where should I need to make a changes (which files)? ? It is possible to do that ? Thank you so much for your answer.