The unicorn Twilight Sparkle, Princess Celestia's most prized student, comes across comes across a prophecy detailing seven magical objects known as the Elements of Metal that is said to bring righteousness and brutality to the land of Equestria. On her way to Ponyville she meets a rather odd earth pony mare named Thrasher, who seems more concerned with practicing her guitar, drinking beer and throwing the empty cans at the heads of ponies.

Starring:
On drums, Applejack a.k.a. Rotten Apple the Element of sick beats.
On lead guitar, Rarity a.k.a. Black Diamond the Element of face melting solos.
On bass, Fluttershy a.k.a. Shrieker the Element of windmilling.
On keyboard/turntables, Pinkie Pie a.k.a. Face Punch the Element of moshing.
On rhythm guitar, Rainbow Dash a.k.a. Tornado the Element of headbanging.
On vocals, Twilight Sparkle a.k.a. Black Magic the Element of growling.
On secondary lead/rhythm guitar and back-up vocals, Thrasher the Element of brutality a.k.a. the one who drinks beer and throws the empties at ponies heads.

And together they form Mystic Princess, but they are thinking of changing the name.
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This an comedic alt. universe story that will follow major plots from the show and a few of my own creation. This isn't meant to be taken seriously and is written for fun.
Rated T for mild vulgarity, crude humor, groupies, the consumption of alcohol and other substances and badly written pony-punned heavy metal lyrics.

I may add other tags in the future as needed.