Grief stricken, and no longer cares about any pony, she doomed their world. Twilight didn't want to have to put her down for good, but it seems the Tree of Harmony is no longer working. The elements have turned useless, and so she and Rarity went to Starlight to learn how to kill with their magic. When I said Twilight and her friends defeated her, I didn't mean all of her friends, and not defeat in the show way. When the time comes, Rarity falters and just can't do it, and it's up to Twilight and Starlight to kill her. The guards didn't actually stop them in their pursuit...knowing the Princess is far too gone mentally, and the curse can't be taken back now. A hard magical battle ensues and Nightmare Moon is overpowered. Even despite her death, it is still eternal night and the curse is still active, until another sun alicorn comes along and is able to raise the sun again. It seems not even Twilight can pull the sun back up and take the moon down, and trust me, she tries. However once she dies, ponies cease to dream at all and the nightmares stop.

I'm sorry, I don't have the time or energy to write right now, but I do want to write and will write something on this as soon as I really can. It'll probably have to wait til my work weekend is over. It'll be in my usual play style, it's just how I like to write things. But because I really want to draw more ponies, I'll probably do these status sheets for every chapter on the main ponies it's about. I ignore the hunger and thirst stat, it's just not that important to me. To emulate the show and for my own personal ease, I am not shading these or getting too complicated with them, however I want to play with poses and the like.

My Luna has the half bat wings too, only they look more like her mane does and gradient is blue to purple. Her ears are also slightly bigger and are the bat ears, they are just facing downwards usually now.
Luna is best princess...I'm so sorry to hurt you in such a horrible way and make you my villain for plot device; I love you Luna and Nightmare Moon, I am so sorry baby :(