An advanced Hyper-Zoanoid; physically unremarkable, he possessed the earlier type Gastal's ability to become undetectable by conventional means (and even the Guyver's alien sensors). In addition to this, he could generate a perfectly spherical, invisible force shield, approximately 100 meters in diameter, which was impenetrable to even the Guyver's weapons; the field even had an abrasive effect, damaging whatever touched it.
Gusyphus was deployed to destroy Guyver-II F; confronting her, he trapped her inside his force field along with four Enzyme-III types, while he himself vanished from detection. However, the female Guyver deduced he had to be in the exact center of the field, and used a form of echolocation (she bounced gravity pulses off its inner surface) to determinate its perimeter. She then simply slashed blindly at the center of the invisible dome, mortally wounding Gusyphus.