King Sombra has Equestria under his control once again. Celestia and Luna have both been defeated from an unknown power, and all inhabitants in the annexed land has been forced into slavery, or death. Only the power of the Crystal Heart has kept the shadows at bay, protecting the Crystal Empire.
Few ponies still rebel against the cruel dictator, who has a new army at the ready. The Revolution was many moons ago, and thanks to the massive force almost all participants were killed.
The survivors linger, rebuilding, getting stronger. Preparing for the battle of freedom and life that will surely come in time...