Superior void knight robe is an upgraded version of the void knight robe which can be made by using a Void knight armour patch on a void knight robe. If used in conjunction with the rest of the superior void armour, it gives a 3% bonus to accuracy and a 7% bonus to damage in the combat style of the type of Superior void knight helm you are wearing. It can be upgraded to a Superior elite void knight robe for 100 Void Knight commendation points by talking to Tyr after completing The Void Stares Back quest.