

Many of his alternate helmets feature names based off Arthurian legend. Excalibur is named after the legendary sword of Arthur King of the Britons.This is further reinforced with the Proto-Armor Skin, which is a near-exact copy of that very suit. Excalibur is similar in design to Hayden Tenno's suit from Digital Extremes' previous game Dark Sector.He is the first of two Warframes with an unpolarized Aura slot, Nekros being the second.

