New Keystone Idea

Lets add a Keystone called "High Mastery" Adds 5 mastery points in exchange of not being able to choose any keystone! Advantages?; You could pick both % pens, or pick flat pen and % pen, or pick the cdr mastery, and so on! it is useful in a sense that it allows you to pick other masteries that you would normally wont be able to pick and it isnt near being OP.