Monga's name comes from the name of the Japanese flying squirrel, the momonga.
Monga is a flying squirrel-like monster. It would have had dark-blue fur, membranes between his legs, ox-like horns, and a mace-like object on the end of its tail.
Much like Varan, Monga's sole known ability was that it would be able to glide around using the membranes between its limbs.
- Monga was replaced by Space Gyaos in the finished film, likely for budgetary reasons. Daiei chose to simply repaint the Gyaos suit from Gamera vs. Gyaos rather than create an entirely new suit for Monga.