Frisk falls to the underground and meets many friends, but will get DETERMINATION get her home?

After an attack that crippled Crystal Prism's wings when she was a filly to later witness the attack on the Crystal Empire...

Crystal Prism, a crippled crystal Pegasus, goes on a journey to stop Shadows Day from coming and she has to find the Elementals.

When the mane 6 go missing there children have to go and stop a pony named Shadowcorn who is a alicorn of darkness. The children learn of the elements of harmony and find that they also represent the elements of harmony.