Kicking butt with the power of MATH!
Twilight as a Calculator from Final Fantasy Tactics. As I understand it, in the War of the Lions release they were renamed 'Arithmeticians'. I only played the Playstation version back in the day, but I never really used a Calculator. I couldn't get a handle on their various formulae for targeting enemies, but having seen another person in a Let's Play use one to basically break the game over his knee, I'm truly impressed with their versatility. They're the true masters of all schools of magic. And use math to do it.