Although drow in general used their darkness power for deception, hindrance, and battlefield control during combat, they themselves were as blind in their own darkness as their enemies. Thus, a few drow warriors learned the kyone veldrin style. As the name "alert in the shadows" suggested, this fighting style focused on sensing the locations and actions of their enemies, even in full darkness, and to attack them with deadly accuracy even whilst effectively blind.
Users of this style often cooperated with users of the luth alur style, even forming special combined attack teams. The kyone veldrin users fought within the area of darkness and the luth alur users shot down those who left.
As the name suggested, would-be users needed to be very alert and to learn how to fight while being blind.
This style is based on the Blind-Fight and Alertness feats in 3rd-edition Dungeons & Dragons.