Sad, Dark, Crossover, Adventure, Alternate Universe
The megaspells detonated. The world died. While most of the surviving ponies did so in underground Stables, the pegasi hid in the clouds. Rainbow Dash, the most celebrated of their ranks, disagreed with their abandoning the world below and left to seek those in need. In doing so, she was branded a traitor. For when Rainbow Dash left, she took the key to the pegasi's continued dominance with her. To retrieve this "key", the pegasi hired a mercenary to bring it back. The mercenary was Gilda, an old friend from long ago. The "key" is Dash's head.