The term Vandal refers to a special classification of existing weapons that have been modified and optimized by the Tenno. Vandal versions of weapons are characterized by their blue-green metallic finish with Lotus branding on the grip or stock of the weapon, modified stats such as increased accuracy, damage, and/or base critical strike chance in lieu of firing rate, and added polarities for expanded modding capability.
So far, Vandal variants of weapons have only ever been offered on a limited-time availability basis coinciding with in-game events, such as Open Beta Celebration Weekend (Braton Vandal, Lato Vandal), the Informant Event (Snipetron Vandal), Operation Breeding Grounds (Prova Vandal) and Operation: Ambulas Reborn (Supra Vandal).
As with Wraith weapons, the coloring cannot be changed on Vandal weapons, with the exception of Supra Vandal. However, some skins can be applied to certain weapons in the group, which then allows them to be colored as normal.