Phobius is a minor character from Battle World. He, along with the other Weekees seemingly siding with Malimors, watch the chaos of the robot vs kaiju war unfold. However, unlike the other allies of Malimors, Phobius was actually a double agent working for Bonivita, Malimors' brother. At some point, it is implied that he eventually informed Bonivita of his brother's teachery, but was eventually destroyed by Dr. Loboto and used to create the Brain Gladiator from his remains.
- Phobius' name is derived from the word "phobia", reflecting his power, and by extension, the Brain Gladiator's power, to amplify and manipulate the fears of others.