Mooncandy's profile

@Background Pony #0D08  
And that’s how some of us like it. :3

The style fits Discord delightfully.

@tehwatever  
At that point, Sombra isn’t even really a “pony”, more an animalistic manifestation of his own malice, until the end of the episode. Undead wraiths being more powerful than their living counterparts is a pretty standard convention.
 
 
As for his army, besides Starlight’s anger bottle, Twilight Sparkle easily enthralled the entirety of Ponyville waaay back when. A common monarch butterfly could hypnotize Opalescence. Fluttershy’s Stare could be amplified to effect an entire swarm of bats.  
Magically controlling an army honestly doesn’t seem that big a deal, even assuming he was.  
It could just be your run of the mill horde-of-darkness or fear-driven army (definitely Sombra’s style there), or technologically mind-controlled (those helmets?).  
Dark magic is, again, a huge question mark. We have basically zero indication what it can do or how it differs from normal magic.