Who is Raistlin from Dragons of Spring Dawning and what is their importance?

Raistlin is a mage, whose use of magic has permanently disfigured him. He has a propensity for evil, but his love for his brother keeps him on the straight and narrow. Over the course of the novel, we see Raistlin become stronger and more powerful. Unfortunately, these physical changes encourage his ambition, and in the end, he leaves his brother to rule the world.