I don't think king Sombre made a big enough appearance. I mean he got the three episodes of his plot but I expected more of a bang from this purely evil unicorn. Luna was controlled by Nightmare Moon, she couldn't help it, and chaos was just his nature. So Sombre is the first antagonist that was purely evil with no implied influence. u w u Maybe he'll make another appearance in another episode. :y
Fuck. I think Sombre is the worse MLP FIM villain evah. And yes I am counting in Snip and snails, diamond dogs and babs seed. I mean really. He had about five lines, which of three were just mumbling groans. He had a red horn, green eyes and purple "Eyeshadoweythingies" I myself would have colored the eyes red too, and the eyeshadows black. He lost without a fight and didn't have any kind of personality. In my fantasies, he has the alicorn amulet first, and since he was a very powerful unicorn in the first place (Unlike Trixie) he was able to gain enormous powers and rule the Crystal empire. Then he gets destroyed in the and, and the alicorn amulet just dissapears. And reapears at the little magic shop. Bujaa! He is very passioned to rule the empire, since he is sure, that to rule a place that great, would make him an almighty ruler, and maybe even help him to take over all of Equestria. He's like an evil Prince blueblood. Selfish, careless and thoughtless, But also feelingless, rude and hooked on power.
What Sombra (apparently I missed the spelling on that one) has going for him is that he has an undeniable presence in form, power, and shape. The reality is that there really was not any need for a specific character to fill the terrible-danger quota that surrounded the ponies and it made the writing for this particular two parter extremely weak. Given his lackluster personality and one dimensional motives it would have been much better if he had a more fleshed out character just in terms of story telling alone. Maybe they will return to this again in future episodes?