Well, there's AI involved, and a menu with which you can change ally AI tactics. Besides, controlling variables for every enemy in a map and applying states would be a pain. If the AI is to be even semi-intelligent it would be better to use a script as far as I'm concerned. Moreover every battle on every map will need to be configured. I've made a TBS through events before, and battle mechanics get pretty complicated pretty fast. A script would be more efficient I think. Anyway, if you think he can do it through an event he's welcome to.