Bresnel is a power-type Zoanoid from the Guyver manga and anime. Cronos attempted to produce an enhanced version of Gregole, but met with poor results. The finished product was indeed stronger than Gregole, but its increased muscle and skeletal density made Bresnel significantly slower. Only five Bresnel units were created before Chronos discontinued its production.

The similarities between Bresnel and Gregole are clear. Bresnel's body shape closely matches its predecessor, though its body is also covered with several boney spikes. Due to its decrease in locomotion, Bresnel does not require the balancing tentacles that Gregole sports.