Visually, Sibilegon resembles a humanoid feline with robotic parts attached to its body. It has a large central console where its chest would be, and its head is almost spherical with binocular-like eyes and a wrinkled, deformed face. It has armour over its legs, and a very long tail.
HistoryKing Flasher and was later defeated.
Shibregon was the thirty-third monster to battle Greenman.
- In Assault! Human, Sibilegon could fire lasers from its fingertip.
- Sibilegon is able to become transparent.
- Sibilegon can open portals into his own separate dimension.