I want to build a system that powers up character based on the skills they learned and used in fights rather than exp. For example, if a character uses magic spells in battle a certain amount of times, I want his mana pool, magic attack, and magic defense increase. All the characters at the start of the game will have certain predispositions to a certain type of skills based on their history but as you play the game I want that the development of the characters to depend on the skills the player decided to teach that character and the skills the character used. This would allow for a character that was previously good at magic to become somewhat good at melee and vice versa. It would also allow negating certain weakness of a character or strengthening even further advantages. Except fighting the character will be powered up through training with experienced fighters, mages, thieves the player encounters throughout the world. The player will be able to leave a character for a day to train with them to gain powerful boosts. Does a battle script with a system similar to this exist? If yes, please tell me the name, if not, how hard would be to code a script like that? I was thinking of just using variables to track how often each actor used certain skills and then make an event whenever the player goes to sleep to check if XY conditions have been fulfilled and readjust each character's stats. Example: Actor 1 used in battle that day: - var 1 = x20 Slash - var 2 = x25 Double Slash Event 1 is called at night and increases actor 1's: STR + 5, MAT -3. MDF -3 , DEF +2, HP+50, MP-5 Reset var 1 = 0, var 2 = 0. How can I make it so a variable is increased when X actor used Y skill in battle?