Nightmare Darkness

Nightmare Darkness Is a Dark Green Pegasus, that rained destruction In Equstria, years before The Mane 6 were born. Where he came from and his Origin are Unknown, the only thing that was Known was that he was the only Survivor of the elements of Harmony during Nightmare Moon's Imprisonment in the Moon, and the near defeat of Princess Celestia herself.

The Unknown Origin
Miles away from the galaxy where the home planet of Equestria lies, Nightmare Darkness was created by an intense black galaxy where all the light was dimmer then the one back in the galaxy of ponies. So this means he’s a living organism of darkness!

First Fight With Princess Celestia
Thousands of years ago, he invaded the land of Equestria with the help of his Flamehound friends. The Flamehounds made sort work of the royal guards who protected Canterlot. Princess Celestia was the only one left at the time to save Equestria. She used the elements to seal up each of the Flamehound invaders but when Nightmare Darkness arrived the battle really begun. After fifteen minutes of flying high above Canterlot while dodging the elemental rainbow that shot out from Princess Celestia’s crown the dark Pegasus unexpectedly flipped around and tackled the Alicorn. They fell through the roof of the same room where The Mane 6 was going to fight Nightmare Moon sometime in the future. He had Princess Celesita at her knees, begging him to stop fighting. Nightmare Darkness just laughed. Soon he disappeared in a cloud of red smoke and was never seen again until the few next hundred years.

Return
During a party that was being held near Canterlot, Godzilla Team was taking part in this. Suddenly the sky lit up red and Nightmare Darkness appeared. The sky soon faded to the normal night sky as Nightmare Darkness hovered downwords. Without the help of Rivera, Godzilla Team and The Mane 6 look in deep trouble. Nightmare Darkness kept making terrible jokes about the Mane 6 of how there so week and puny. Suddenly, Princess Luna appeared in her Nightmare form to help her best friend, Nightmare Darkness out.

Defeat
The Mane 6 managed to use there Elements to seal up the evil Stallion even without the help of Twilight Sparkle.