Today was the annual migration of all the Inflatable Creature breeds, from birds to sea creatures, etc. They've all came to live in the city of Riverworks.

It's been said that these special sentient inflatable creatures can take the appearance of their rubbery anthropomorphic counterparts, either it be realistic animals, or even well-known creatures from the media (MLP, Pokemon, Sonic Franchise, Digimon for example), and have the ability to interact with non-inflatables creatures.