Though not yet a band, the Do-Re-Mi Band had its origins in Rattle Diva's career as a musician for Big Green. In Pandaffe Castle, it was her considerable rage at not being able to complete an uninterrupted concert that led her to briefly ally with the pandas and giraffes against Big Green. However, when the pandas and giraffes agreed to peace, Rattle Diva returned to Big Green and began to play alongside the Panda and Giraffe Kings.
In Frog Castle, another concert was interrupted, in this case, by the news that the frogs were tormenting humans. First Squad set out to stop this, and were followed by the scorned Do-Re-Mi Band. Ultimately, The Do-Re-Mi Band had a musical competition with the frogs, during which the frogs were so impressed that they agreed to join Big Green. The frogs subsequently joined the band.