inthepower

Hey guys, hello. I'm new at this forum, and I'm making a custom server based at Old Times RPG, like Tibia, MU, etc... Well, what i'm doing is a system when you use a skill a number of times it evolves. Ex: - You use Fireball 10 times at level 1 and go to Fireball level 2 - You use fireball 100 times at level 2 and go to Fireball level 3 - You attack using a blade 1.000.000 times and you Sword Mastery go to level 1. - You attack using a blade 1.500.000 times and you Sword Mastery go to level 2. Anyone knows any system that look like that? I'll be greatfull if someone help me at this.