The strengthened version of the Electric Fox that appears from the Lightning Attribute Update Box, Gamma revealed these Black Foxes in his second battle against Hayato Gokudera. Their fur turns pitch-black and they become clad in armor. Gamma refers to this as the true power of his Box.
Gamma promised himself never to use this form for the Millefiore Famiglia's gain. He thus gave his Update Box to Yuni, asking her to only return it when it was once again time to use it for the sake of the Giglio Nero Famiglia. Prior to his departure to the Merone Base, Yuni entrusted it to Genkishi with the request of giving it back to Gamma.
All of their abilities are of high-power, but it is impossible to draw out their full performance with a Ring below B-Rank. They can electrocute targets that are trapped between them and generate enough electric energy to fill an entire room. They were also shown to be able to levitate a person of small size, possibly by means of a charged electromagnetic field.
- Elettro Net Shield - Thanks to the Solidification Attribute of Lightning Flames, the Black Foxes can turn themselves into solid shields to block attacks.