Here, in darkness of my prison, unmoving, I have laid here for hundreds of years. A god does not need food, water, air or sunlight. Eternity can be unbearable if you have nothing to keep you occupied. And what can you do, if you are locked in dark, cramped chamber, surrounded by all types of magical barriers?
You start looking for a gap.
I still remember my sweet, beautiful Nightmare Moon, so bright and so proud. She would smash these locks, break the barriers apart. Leave nothing but slightest embers of magic, which would melt into her magnificent black mane. And then, she would make night and shadow itself kneel before its true goddess. But I am not strong enough. My powers pale in comparison to those of Nightmare Moon.
The only thing I am good at - is spreading seeds of chaos. To look for contradictions and create strife and discord.
That is why I'm not fighting my barriers. No, I listen to them; I seek out the gaps between two layers of defensive magic. Cracks within the shields which separate me from the outside world. Gaps, no bigger than a needle, where an almost unseen dissonance can grow in the rhythmic buzz of the magical fields.
I do what I am good at I enhance contradictions, deepen weaknesses.
There is no need to hurry - I have all time in the world. Music of bolts becomes a cacophony. Instead of working together, parts of my prison begin to interfere and break onto themselves. Harmony slips away, and in her place appears the beautiful, wonderful, unpredictable and terrifying discord.
The barrier restraining my senses will fall first. Vision, hearing and touch, slowly my omniscience returns to me. My perception escapes my prison's limits.
My senses, I unleash them, and, as my loyal servants, they travel around Equestria, searching for Elements of Harmony, and the one who imprisoned me.
I will not come back unprepared.
I see six wielders of the Elements. Nothing but mortal ponies, who somehow obtained power beyond their imagination. My dear Nightmare, why?
"Why?" I whispered, as feeling of her presence has gone, taken away by the Rainbow of Light. Once more, without a second thought, she had taken to the fight. Once more, too proud to hide. And once more, despite all her words, not a single pony killed
I am not going to kill anyone either. The dead are useless to me.
The dead cannot watch my triumph.
Senses, weakened by ages of imprisonment, are returning to me. I do not need majestic speeches, nor powerful magic. I won't even use my influence yet. For now, all I have to do - is to wait. Let wielders of the Elements lose vigilance, let them forget about their power and return to ordinary life. And at that time I will look for rusted links in chain of their friendship. Now I understand that was the only right decision. Elements of Harmony are too pure to be harnessed by a mere mortal. Contradictions have rotten our "heroes" from within and now their fall is only a matter of time.
After all, they are just mortal ponies. And every mortal has its weakness.
Honesty tried to fulfill all promises she gave and, unable to deal with impossible task, failed each one step by step. Laughter's doubt in the loyalty of her friends brought a shadow over her joy, a shadow that I could manipulate. Generosity almost ruined her hard work and reputation in a vain attempt to make her friends happy. Loyalty became a miserable shade of herself, once she faced the anxiety of a crowd and the betrayal of her friend. When Kindness realized that could not force animals to love her she turned from shy little pony into a raging beast. Finally, the element of Magic, this pathetic bookworm trembled in terror when she finally understood, that some questions in this world can't be solved by a spell or an ancient tome.
So now that I have acquired my instruments, all Equestria will shake! For I am about to play my symphony of discord.
What will Honesty do if in moment of danger she will have to choose between her friends and her family?
How would Laughter react if I'll turn everyone against her?
Will Generosity still remember about her friends, when she achieves fame and fortune she always desired?
Loyalty, when on one hoof lays the fate of Cloudsdale and that of your friends on the other, to whom will you be loyal?
What if Kindness suddenly realized that no one needs a shy yellow pegasi that world has left behind many years ago?
And, finally, what will Magic do, if she is forced to stand alone? The mere sight of me will break her.
I will not engage even in a single battle. Let's leave this opportunity to others. Griffins, who have always wanted to bite a piece out of Equestria. Buffalos, who have been forced to tolerate ponies far too long. Dragons, who merely need an excuse to reclaim the mountain peaks, where they laid for hundreds of years, until first settlers appeared. Finally, even ponies will turn against their princess, in order to end her prolonged reign. Just a few manipulations and this powder keg will explode.
I am not going fight.
I'm just going to do what I am good at.