1. Nearly as powerful as Discord and Tirek (Facing BOTH Princesses, making a whole kingdom vanish, growing anti-magic crystals, using mass brainwashing, giving life to a cursed door, making a pocket dimension of nigh-endless stairs, etc.).
2. Maybe the smartest villain (Look at all he did to hide the Crystal Heart! Twilight and Spike got VERY lucky!).
3. Dead serious (No speeches, no arrogance, etc.).
The biggest waste of character in the show. Seriously, the moment I first saw him I was so excited and thought he'd be a badass villain... instead we get a growling smoke cloud that barely has any screentime, development, or, well, anything for that matter and the episode is instead padded with unnecessary songs that felt like filler, and he's beaten almost immediately after he actually arrives.
Pictures as great as this make me wish more was done with him or that they'd bring him back.
Umm, hi my mighty great sir. Uhm, I planned to use your pic for story, but I didn't know who it was from and was honestly determined to find who was the owner. But today I have finally found who it belonged to with a bit a searching (Now that I found you I could finally refer you to the story) and I now come to you to ask if I may use this pic for my fanfic on King Sombra's past. I would certainly link you to it of course.