A Light web was an exceedingly dangerous, powerful, and difficult spell web that only the most powerful of the gifted were able to cast.
Light webs could be used as both an offensive or defensive measure. If one were to weave a light shield around an object, it would prove next to impossible to breach, while if a light web was woven around a certain person or area, it was possible to cause a great deal of devastation in that vicinity.
A light web woven in the thousands of years following the Great War was capable of destroying a building about the size of the Confessor's Palace. However, during the battle between Zedd, Adie and the Imperial Order, Zedd was able to trigger constructed magic from the time of the Great War to kill over half a million soldiers, highlighting the enormous amount of power held by the wizards of that time.