Why does she seem like both the nicest and most evil pony at once ;-;

@Prometheushunter2  
I imagine she’d be a combination of the body of Daybreaker:  

 
And the personality of this:  
>>1487389t (deleted)
 
“I am not Celestia anymore.”  
———————————-  
Unlike Nightmare Moon, Magmare Sun is less about over-dramatic speeches and maniacal laughter and more about setting you and everything you love on fire. She doesn’t gloat, she doesn’t smile, she doesn’t even talk-she just comes on steadily and surely, malevolent and murderous. With all the power of the Sun.
 
Whereas Nightmare Moon’s primary attacks were lightning and magic blasts, Magmare Sun uses earthquakes, geysers of molten rock, and fire in her attempts to raze Equestria to the ground. What brought about this transformation in Equestria’s kindest sovereign? And how can she possibly be stopped?

@Phantom Rider  
I like to imagine her coming back with her eyes completely gone to do the blinding light leaving nothing but horrific sockets, With her skin is completely charred do to the heat, with her powerful magic and and shear willpower fueled by hatred being the only thing that kept her from disintegrating. As for her mind…. well, a thousand years of being burned alive isn’t going to leave your mind in just ONE piece

@Prometheushunter2  
Enter Daybreaker or similar, worse than NMM?
 
I can dig it.

Even with all the seals in place I get the feeling she’ll be seeing her “dearest sister” again someday. She forgets her sister is stronger and smarter than she is. And is a lot more rational. The moon may be a dead wasteland but up there Celestia has one thing, time, LOTS of time. Time she could use to increase her skill and power to a high enough level to escape. And if she gained enough to power to break multiple seals holding her on the moon… well… the likelihood of nightmare moon, let alone the whole of equestria surviving whatever comes down to say hello is VERY slim

@Twilestia  
It’s more like a sociopath has a mental condition which can be cured after therapy, while psychopaths have something wired wrong in their brains and it’s absolutely impossible (at least by today’s standards) to cure.
 
I brought in canon Luna because all said and done she is the basis of NMM’s character and by her reactions in the show we can tell she’s not a psychopath. She has a ton of mental issues, though.
 
I think my comparison to our world falls flat after all, because unlike humans, ponies are creatures of EXTREME habits.  
We see this countless times in the show, how they see change as something bothersome. So most of them would just stick  
with what they know over what they think MIGHT be a better option.
 
Daybraker is a thing in canon, after all.
 
 
Oh, and of course it’s going to be Tuna. Silfoe is dependable when it comes to that! <3

@Background Pony #0C89  
I am talking about this universes NMM not the show one. I didnt (and neither did you in your question) mention the canon version at all.
 
And i could be wrong, but all that makes the difference between a sociopath and a psychopath is that the sociopath has a conscience (although that doesnt mean he/she will acknowledge it) and the weaker (? or not by now) theory that sociopaths are shaped by their environment while psychopaths are simply born.
 
Thats why i said it could be as a alternative that she was born that way (so maybe a psychopath instead). Even here where we see more of her evil side we cant really tell that much. Not like in the end its the main focus of this au comic either.
 
 
As for history, even during the World War 1 and 2 periods our ancestors did and thought things we would be appalled by today. We do things in the future (maybe even near one) will think the same about. We live in a fast moving world and society keeps evolving fast as well, for better or worse depending on who you ask.
 
But what remains universal throughout history is that if there is a (seemingly) better alternative that people might just take it. NMM seems to have quiet a totalitarian regime going on so there would probably be many who would gladly oppose her if a proper chance presents itself, especially in the more remote areas. A chance like another Alicorn capable of manipulating the sun and moon appearing.
 
Heck, from AJs comment we can see even as close (or not? no idea/dont remember where actually NMMs castle/base is in this universe, either everfree or Canterlot i assume) as Ponyville there is open enough dissent. Maybe my theory of a good chunk of the (world) population dying is right and then there would be quiet a bit of issues for NMM to have an actual presence all over her domain.
 
 
But its all empty theories that i just like to think about, will probably just end up being a AU TUNA comic since its Silfoe we are talking about. :D :P

@Twilestia  
So you don’t know the difference after all.  
We can’t really tell ANYTHING about canon NMM’s mental state from just one scene in one episode.  
What we can tell about xanon Luna AFTER is that the elements might have destroyed her psyche to the point  
of crippling her self-confidence. Luna was TORTURING HERSELF MENTALLY out of guilt, for heavens sake!
 
The NMM in this comic gives us a few more hints about her mental state.  
And yes, this NMM shows signs of a high-functioning sociopath.
 
And 1000 years is a pretty long time, all things considered. Just think of our world a thousand years ago,  
and about the things that we now consider barbaric. Heck, we even see the world as recently as 200 years ago  
as uncivilized. In that time a lot of changes could have occurred even to the ecological system of Equestria.
 
Heck, this Celestia will feel even more out-of-time than Luna did in canon.  
In canon Celestia did everything to make Equestria look somewhat similar to the one Luna knew.  
NMM did not have that in mind.

@Background Pony #0C89  
She herself for the most part with a small bit of others, and thats a maybe. Or an apternative is that she was born that way and fate sucks. She did get a concentrated blast of harmony right through her brain. Maybe thats the reason she didnt end up just killing everyone.
 
 
There is only so much you can reshape basic needs like food and such. “Right and wrong” dont matter much if the masses are against you. So you have to keep a tight leash on them and keep them down.
 
But with the return of Celestia coming…

@Twilestia  
I’m glad you can tell the difference between sociopath and psychopath.
 
Who’s fault is it, who is it that shaped her this way?
 
And NMM won this particular scenario, thus reshaping right and wrong

@Makarosc  
Or more likely the crops died from lack of sunlight, majority of the (world) population died off, danger of everyone dying instead of worshiping her every move like she wants forced her to swallow a slice of humble pie and raise the sun for at least some time.
 
From her overall behavior we can see shes still a sociopath, just forced to control it better to get what she wants.

@Twilestia  
Nightmare probably created some sort of famine after defeating Celestia then solved it by making everyone part bat to end it some how and sorta saved everypony

@Hugobertington.Esq  
The Hell?

When I look at the last panel, Nightmare moons’s eyes look sunken in with like a lens over it which the moon becomes a sticker placed ontop of that lens. I am seeing depth which I know isn’t there. It just looks very odd. Nice smile none the less.

@Background Pony #F67B  
Naa NMM is Luna it was only when she was at her lowest after Twilight defeated her that she admitted she was wrong. If you remember season 2 Nightmare night Luna tells Twilight that she took her dark powers from her

@Background Pony #F67B  
Sombra would probably make the biggest gains in this universe. He would simply re-instate his reign of terror unopposed since I doubt NMM would care about the northern border since it would be nothing arctic wasteland until then. And I think that if NMM was alerted of his return would take a different approach on him, perhaps using him like reformed Discord or even striking an alliance, causing a case of honor among demons of darkness.

question  
if sunbutt’s butt is the sun  
and sunbutt was banished to the sun  
was sunbutt banished to her own butt and  
if so  
is her butt now another sun but still the same sun on to which she was banished  
infinitely recursing smaller suns and butts  
all the way down?

@Background Pony #8743  
Killing her would have been the best choice. Demoralize and drive utter fear into the subjects, no chance for her to return and no danger of her turning the people you control against you in a manner that could really threaten you.

@Twilestia  
I mean that there are many other ways to get rid of your sister especially when you are not hampered by the moral framework. And if she chose this one, it is unlikely that she expected her sister to peacefully spend all this time in stasis.

@Twilestia  
Then what is the point in this exile? I understand that Celestia could immerse his sister in stasis, so as not to hurt her. But why would NMM be doing it, obviously not having good intentions towards her sister

@Background Pony #8743  
Or the banishment is spent in a sort of stasis, no thought no nothing? Do we actually know how it is handeled, either the EoH banishment or whatever method nmm used.

@Background Pony #F67B  
@Twilestia  
If NMM spent her exile in agony and hatred, Celestia being much more restrained and prudent could spend his exile in training and developing their magic powers. And returning after exile not to fight with your sister, and become a lonely warrior who will protect equestria from all enemies.

@Background Pony #F67B  
If he drains enough magic before confrontimg them they would still be boned, especially if it happens before twilight is even born.  
Discord and Chrysalis end of the world events would pretty much happen shortly after the usurption as thats the best time to strike. While equestria would be torn apart and severly weakened.

@Background Pony #8743  
Well, if Tirek does appear, then NMM and Twi are pretty much screwed because Tirek can just suck out their magic and I’m pretty sure they can’t rely on the rainbow power from the finale of Season 4. But they could just conjure up a spell to send him back to Tartarus.