@Shoto  
hmm maybe thats the point maybe the artist left it ambigulous on purpose so each veiwer could decide what it was for themself

@Prysmfox  
huh. i wouldn’t be able to tell you that from the picture itself. they really do look like nightmare rarity and midnight sparkle, and the source gives no context.

@Background Pony #B837
 
@Shoto  
the tags are in error, this is meant to represent the lunar trinity  
which is as follows  
Woona, luna, nightmare moon, the one on the viewers left is woona, luna’s inner good all things innocent and playfull, woona, the one on the right is nightmare moon representing all of luna’s vices both the simple such as desires and lusts, to the grand such as her wish for eternal night, nightmare moon  
the one in the back is luna herself, hence its blank eyes because its eyes are looking out thru the main body, i dont know what the gold gem is supposed to represent in this particular iteration

@Background Pony #B837  
pretty sure the top most character is midnight sparkle i might be wrong tho

I simply adore this concept! More of magical mane tempting Luna! Beautiful colors! Too bad the watermark is directly in her face though.
 

 
P.S. Where’s Twilight in this? I can’t see her.

Very nice! Certainly an interesting concept.

Such a lovely art…

This is awesome.

nightmare on luna’s left, desire (dream)on her right, and foresight (prophecy) above her  
@OctiLuna

Very interesting art…  
The first head, on Luna’s right, looks the most like Nightmare Moon. The one higher up on Luna’s left side could just be another form of Nightmare Moon, or it could be the representative of the Tantabus. Not sure though.  
Regardless, awesome art.