Sicemon

Sicemon was a planet covered in vast grass plains upon which the Rebel Alliance had established a base. The were giant, whale-like flying taxis gliding around in the cities of Sicemon.

Behind the scenes
Sicemon originally appeared in the first draft of Star Wars: Episode VI Return of the Jedi. The idea of a grass planet and several pieces of concept art drawn by Ralph McQuarrie and Joe Johnston ended up being reused to depict Alderaan in the Expanded Universe. The concept art for Sicemon would later inspire Maridun, a grassland planet featured in Star Wars: The Clone Wars, an animated television series.