No Magic? No Problem!
To keep it simple, and short, our protagonist was someone who couldn't use any magic in a world where everyone could.
Until, an apple fell onto his head, and he remembered that he was a scientist in his previous life. To dismantle, analyze and synthesize is what he was known for, and exactly what he was going to do in this wonderful fantasy world where the laws of physics didn't matter.
Bless be to the man who figured out the laws of magic instead. After all, what use is a fireball, when you can analyze, and dismantle it before it's even being cast?