In “Legend of the Seeker”, the Mord’Sith have the power to seize and re-direct magic aimed at them. Zeddicus Zu’l Zorander (Bruce Spence) knows this, and yet still occasionally shoots wizard fire at them.
Don’t do that.
It’s like old-school Green Lanterns versus the color yellow. Eventually even those morons learned to use intermediation.
You can’t affect your foe directly? Or, worse, he can turn your power against you? Accelerate stuff at him. Rocks, freight trains, whatever. Zed, who has a vast array of spells and is supposedly the greatest wizard in 3,000 years, has yet to figure this out. He should be able to beat a hundred Mord’Sith, instead of getting his buttocks kicked by any one of them.
Telekinesis is your friend. T.K. for the K.O.
This has been a public service announcement.
World's Only Rational Man 
Zedd never faced them in the books, though. Richard (who didn’t know about them) did, and was captured. When Zedd runs into them, Khalen is running interference and the Mord Sith find every reason to go elsewhere at that time.
Scriptwriters want flashy action. See 24.
Oh sure. And I love flashy action! But intelligent action beats stupid action. If they’re free to change things from the book, they need to make the changes non-stupid.