Galvo

 is an abnormal from Hollow Earth who came to the surface as part of the invasion force led by Fallon and the Crixorum.

He was of very small stature, but had extreme physical strength thanks to the abnormal molecular density of his body. He was also prone to violent flatulence.

Unlike many of his fellows, he was unwilling to return to his home after the truce with the Sanctuary Network, and remained adamant in his determination to reconquer the surface world from the humans. He even tricked Bigfoot and Will Zimmerman into leading him to a group of abnormal refugees, only to kill them once they were in range of his weapon. He then tried to kill Bigfoot, but was stunned by Will just in time, and taken into custody at the Old City Sanctuary.