Looking for a series where the main character (MC) wizard has water and air magical abilities, and uses them when battling a fire and earth wizard to freeze them both inside a cliff. The MC defrosts first and goes on a quest to find another fire and earth mage.
The catch is that there are none, because they go crazy, so when they show up, the medieval society hunt them down. Along the way, the MC finds a woman who can control and enter dreams.
Later in the series, it is revealed that the process of training or developing magical abilities involves two moles that are mentally connected to the trainee inside a spaceship. One mole is burned and the other buried alive.
I read this in high school, so back in the late '80s and early '90s.