How do I make magic fire?

I am very (very) new to this and I was looking through the various Spheres to find neat ideas. However, when I was reading the Forces section it struck me that it seemed quite limited, and it looks that Forces on its own largely summarises as: bigger and bigger fireballs, or alternatively bigger and lightning bolts, depending on the mood of the wizard in question. So I was wondering how one would go about imbuing forces with magical effects? Say, if I wanted to make a flame that stuck to someone and never went out? Or a lightning bolt that caused lingering pain, paralysis and poisonous wounds, or, to take a page out of WoT's book, fire that burns someone out of time.

Indeed, is there even any point to such things, or are you better off just using other spheres for similar effects with less effort?