Balloon Legion

Overview
Balloon Legions are monsters that tend to hover in the skies of Melromarc and spawn Balloons. They're often dismissed as strangely colored clouds when spotted in the sky. According to Rat, Balloons break off from the larger Balloon Legions and can act independently after the separation. The Balloon Legion floats freely in the sky, rarely coming to the ground by their own volition. On the contrary, the numerous Balloons they spawn are very frequently found causing trouble on land.

Trivia

 * Balloon Legio are mentioned only in the Web Novel