Rage Ravine is a location situated somewhere within Avalice.
After Lilac receives the phone call from 'the big Panda guy', our heroes travel and trek through Rage Ravine to find the general and his meeting point. Eventually they do, and they ultimately meet up with General Gong at the meeting grounds. (though how they got there is ultimately cut. Only the scene where Milla and company finds the general remains.) After discussing their plan to retrieve the stolen Kingdom Stone, the girls and Torque ride their plane towards Fortune Night, in hopes of catching up with the thief before it's too late.
Rage Ravine was meant to be a stage in Freedom Planet. It was cut for unknown reasons. It is also currently unknown how the entire stage layout would appear or the current placement of enemies would be. The data can likely still be found within the beta builds. Due to the data, it appears this would have been the third Stage played under the name Rust Yard (preceding Relic Maze, and being preceded by Fortune Night; making the latter the fourth stage, and so on). Despite this, scenes of the location can still be viewed in certain cutscenes, such as the story mentioned above. The soundtrack for the stage appears intact, but ultimately went unused.