The Power of the Tech; book 3 of The Black Blade Trilogy

The new color guards from The Havens traveled across the Rolak Plains to achieve a great victory, but they payed a hefty price. Now those who remain must decide whether to take on a new quest to try to destroy Xor and the black blade once and for all, or to return to The Havens and await his wrath. The choice might seem easy, but easy choices aren't always the right choices.