Few words about mages and magic

Mages don't need to remeber spells every day, but they have limit to cast spell. More times and more powerfull spell is cast, than they faster reach their limit. It could be grow by staffs, rings and magic jewel or... By living creatures forces. In control collars, that tool take energy from mage to block his magic. If mage cross his limit, he can get hurt by himself or ewen die.

Most mages decided to master max. Two or three school of magic, because when they mastered some kind of magic, they can throw more spells and more powerfull than complety beginner.

Curses are possible in this lore, but to be cast they have to be throw by powerfull mages and prize of any kind isn't low. The curse for eternity except skils and power of mage, need also sacrifice of something important for the mage. It is serios spell, so it will be using only for worst enemy.