Before I take on the Season III episodes, I wish to first talk about a few of the more controversial issues raised. To start, I want to discuss the issues that some fans have with Sombra.

I don’t think he was that bad a villain in many ways. The ironic thing here is that Sombra, easily the most disparaged villain of the series, is the only one who did not give the Mane 6 victory on a silver platter. He loses despite, and not because of, his actions, none of which are stupid. I wish that I could say as much for Nightmare Moon, Discord and Queen Chrysalis. The other point is that the Mane 6 only won through a series of very lucky coincidences that no villain, no matter how savvy, could have predicted or planned for.

 In part, I understand why he gets a bad rap, because he is (on first viewing) a very poorly characterized villain. He simply isn’t shown to have the depth of the other villains. His lines are extremely limited, and he didn’t get to do much in the episode itself before blowing up. One thing he did do, however, is disable one of the only two ponies who are keeping him out of the Kingdom he wishes to retake. And I don’t think that’s an accident.

 Here’s my reasoning. He couldn’t have known the Mane 6 were coming. He has been camping right outside the empire, trying to get in. Shining Armor did know the Mane 6 were coming. When he left the city, Sombra would have seen him first. Being a unicorn himself, he would know that Shining Armor must be the one keeping him out, since the Crystal Ponies don’t have the magic necessary to protect themselves without the Crystal Heart. All of this makes me think that Sombra was there to attack and disable Shining Armor, who as far as he knew, was the only one stopping him from reclaiming the Crystal Empire. That implies that Sombra is not just an animalistic shadow (har har) of his former self, as some claim, but a reasoning, self-directing villain, as much as can be claimed for any of the other foes the Mane 6 have faced. His plan, if indeed that is what we are meant to assume it is, is not only clever, but it works. At least, it would have if Shining Armor were the only unicorn protecting the Empire. So that runs counter to the claim that “he doesn’t do anything in the episode”.

The thing about Sombra is that most of his villainy and planning was set up before the episode even begins. He removed the relevant page from the one book mentioning the Crystal Heart. The entrance to where he kept the Crystal Heart was hidden and only someone with dark magic could open it. None of the crystal ponies have horns, and presumably they have no magic. Even if they did, it's far more likely to be light magic. The next trap, a door leading to the victims worst nightmare is more fiendish still, because it's triggered by using dark magic, which the victim would already have been primed to use because it got them results a little bit earlier. It's also an insurance policy against a pony having dark magic skills to begin with. The only way to escape it is to have someone else come and snap you out of it.

Sombra also created a delaying staircase that Twilight just happened to have a spell to deal with, which she had never demonstrated before this episode. Then at the end of that, he had an alarm set up around the Crystal Heart to let him know someone had found it. It's not an automated trap, though. When Twilight triggers it, we are given a brief glimpse of Sombra reacting and then casting the spell to trap Twilight. So, again, Sombra is acting and doing things in the episode. This also hints that he might have even stronger magical power than Twilight does. He's savvy enough not only to consider the possibility of her teleporting, but also has the power to override her when she tries it.

So Sombra plans intelligently and craftily, destroys information vital to his enemies, is strong enough to negate the magical ability of both Shining Armor and Twilight, actively targets those who stand in his way and only has victory snatched from his grasp due to pure luck on the part of the Mane 6.

First, it's lucky that Rainbow happened to bump into the librarian pony just as she remembers the real Crystal Heart. It's lucky that Twilight just happened to bone up (stop sniggering, please) on gravity spells for her "test". It's lucky that her last-second dive for the Crystal Heart ended up not with her grabbing it, but instead knocking it away from the trap. And last, certainly not least, it's lucky that Spike was around to save everyone.

Spike is the key to victory throughout the whole episode. He breaks Twilight out of her Demon Door trance; his own experience with it clarifies how it works; he points out that the staircase is just a delaying tactic, and finally, he's on hand to grab the Crystal Heart while Twilight is trapped.

To summarise, Sombra's pre-planning and actions in the episode would have resulting in him winning if not for the interference of Spike, a healthy dose of unanticipated good luck for the heroes, and a last second wife-toss, all of which is enough to ruin anypony's plans.

I feel saddened that fans allow his lack of discernable personality (beyond that of being an evil dictator with an unhealthy fascination for dark crystals, of course) to distract from the fact that he was actually very effective at being villainous.

Keep chasing those dark crystals, everyone.