451 degrees fahrenheit is only relevant when you're using heat, when you use magic (or Magic) it doesn't matter. When you want something on fire, you get fire.
For example take Return to Ravnica's Explosive Impact. On it you see a Boros knight doing what Boros knights do best - punching! This time the Boros knight is punching down and using his red magic to create a blast of fire that eviscerates his enemy.
As a member of the Boros guild, I heartily support this action and this plan.
From the art description I'd like to highlight the following line, "How'd you liked to be punched in the face with a red-hot fireball?"