Creating a new spell was something that mages rarely did in this day and age. Due to its long history, most situations that required spells had been solved hundreds of years ago and then passed down.
There are some mages who are researching ways to improve current spells to be more efficient, yet other than the mages with the special element, mages don't create their own spells because it's a waste of time and dangerous.
Why would they waste years of their life to create a spell that would more than likely be worse than the ones that had gone through centuries worth of tempering?
The spell that Jayce created during the mid-term to finish off the Dungeon Boss was of the lowest tier and could barely be considered a spell by most mages. Although it had plenty of utility uses, it lacked offensive capabilities due to the numerous limitations, wasn't defensive, and could easily be spotted by the opposing party.
