--Thunder Bolt--

I think the most parsimonious explanation is that Equestria is a simulated environment--either a giant Truman Show, or a Matrix. This explains "magic," Pegasi being able to fly in defiance of physics, some ponies being able to stand on clouds while others can't, Pinkie's unusual abilities (she's The One ), and the juxtaposition of the odd cosmology with apparent knowledge of real physics (relativity equations on blackboards behind Twilight, Pinkie using the word "galaxy" in one of her songs, I don't recall which offhand). The Princesses (and during the Hearthswarming Eve era, the unicorns working in concert) are able to control the "sun" and "moon" because they can basically pull the levers of the general simulation to a greater degree than most. The EG HumanWorld is another simulation running within the same system, which is why Twilight and Spike are able to upload their minds into completely different "bodies" (which would, realistically, have very different neurology) and have that actually work. Or, you can just use the MST3K Mantra.

Um... Well. I guess it settles the question of whether or not an earth pony could be a villain. Otherwise, I'm not really a fan of the gore and destruction, and I kinda have to wonder about someone who hates the message of FiM enough to put that much effort into attacking it.

My headcanon is that unicorn magic is only the most obvious type, and that there is a subtler type of magic that everypony can access. For now I call it "implicate" magic, to use David Bohm's terminology. Most if not all species in Equestria use implicate magic in one way or another; parasprites for reproduction, dragons for fire-breathing, phoenixes for resurrection, pegasi for flight that would be otherwise physically impossible given the size of their wings, etc.. Earth ponies can use implicate magic. For example, Applejack uses it when she bucks apples. Apples wouldn't naturally just fall out of a shaken tree and land neatly into buckets placed under it. Pinkie Pie is a master, as is Discord. Notice that he doesn't wield magic through his horns unicorn style. Most ponies don't know implicate magic exists because it's like water to fish. Unicorn magic appears to be a lot like the magic of the Hermetic tradition; there are grimoires and mathematical-geometrical symbolism, specific "spells" that must be consciously understood and properly performed. It is very abstract and cerebral. Implicate magic works more like qi in the Asian martial arts, or animist shamanism, or "the Force" in Star Wars. It works more through the emotions and the subconscious than through the intellect. Most ponies and creatures use it unconsciously. Rainbow Dash uses it to perform sonic rainbooms; she thinks she's just being really athletic with her wings. Fluttershy wields it to produce The Stare. Zecora uses it with rituals and natural elements to create her potions. In Magic Duel we also see that she knows enough to become a Yoda figure for Twilight. An earth pony who was a natural talent like Pinkie Pie or Zecora, noticed that s/he had unusual abilities, and began a regimen of study and practice could well become very powerful, in my opinion. Just imagine an anti-Pinkie Pie, with physics-breaking powers and the ability to spontaneously conjure a Despair Cannon (or Mind-Control Cannon, whatever) instead of a Party Cannon. Emerging from potted plants at will, able to stalk like nobody's business (even Rainbow Dash couldn't outrun Pinkie), able to conjure illusions like Zecora (Luna Eclipsed, IIRC)... Throw in a new ability or two for spice, like an Earthbending power (for those who haven't seen Avatar: The Last Airbender, the ability to manipulate earth and rock at will), and some cunning in its use, and you have a villain at least as formidable as NMM or Sombra. Even a fairly modest amount of power in implicate magic could go a long way for an earth pony villain, because they would have the element of surprise. Nopony expects a "mere" earth pony to be a threat...which could be a pretty good motive. Say, they can create a mind-control potion, or they can shape-shift (as two of the Pinkie clones do in Too Many Pinkie Pies). That, plus some high-octane intellect, maybe some minions and Steampunk mechanical contraptions, like massive armored robo-pony vehicles (call them Trojan Horses ), and you're good to go.

Ears: Phase 1: 'AAAAAAAAAAAAAAAAAAAAAAAAA......!" Phase 2: *learns to rotate them like a cat or a horse, notes the interesting effects of being able to selectively aim hearing* "Huh...okaaayyyy...." Phase 3: "AY! WHY COULDN'T THIS HAVE HAPPENED IN TIME FOR ME TO GO TO BRONYCON?!" Phase 4: "Whelp, good thing I have a top hat. My employer is just going to have to accept the fact of me going full-on Steampunk henceforth." Horn: Phase 1: 'AAAAAAAAAAAAAAAAAAAAAAAAA......!" Phase 2: *learns that I can't do magic with it, yet* "Huh...okaaayyyy...." Phase 3: "AY! WHY COULDN'T THIS HAVE HAPPENED IN TIME FOR ME TO GO TO BRONYCON?!" Phase 4: Depends on its initial size and orientation. If I could hide it for awhile under my top hat or a beret, I would probably do that so I could buy time. I would start putting in the time to practice magick instead of just having books about it. I'd start studying NLP, hypnosis, qigong, and practicing public speaking. Phase 5: Write a book and become a rock star of the New Age lecture circuit. Could Deepak Chopra compete with a real, honest-to-goodness unicorn horn? I don't think so. *mischievous grin* Phase 5 (alternate): Learn stage magic and become Human!Genderflip!Trixie. Either way, the sudden appearance of new bodily features would be proof that magical metamorphosis is possible and apparently under way. I would avoid interfering (attempting to surgically remove the ears or horn) because, who knows what the effects would be? In terms of Genre Savvy, I don't recall ever reading or seeing a story where someone starts turning into a superhero or magical being, tries to stop the transformation and continue their previous mundane life, and had that work out for them. Imagine the disappointment if, say, you cut off your uni-horn only to find out six months later that it could have worked magic if you'd just let it grow a little longer, or that you complete your pony transformation and get brought to Equestria, only now your unicorn powers don't work.

I think an earth pony could be a convincing if she or he has magic like Pinkie Pie or Zecora, only more powerful and applied to evil purposes. Or they could have superequine strength and/or speed, perhaps attacking with a horde of warriors. Like the Mongols, but without the riders. Or be a pony Batman/Lex Luthor, with lots of gadgets. Xanatos-level evil genius wouldn't hurt either, though that might be a bit hard to pull off in a show for young children. I think a "Nightmare Pinkamena" (Pinkie Pie turned to evil somehow) could be a genuine menace. Or a Pinkie clone that somehow managed to avoid being rounded up with the rest of them.

It isn't just Nazi "logic." It's the "logic" behind pretty much every atrocity committed by the human species. And the core premise in this case, that the ponies are inherently superior to us? I'm not buying it. David Brin offers an excellent rebuttal to this sort of thinking in the latest post on his blog: