Concerning the Season 6 finale.

Contains spoilers below.

So long Changelings, you were great villains. Sad to see you go. On the other hand, way to go Chryssie! Honestly, Queen Chrysalis is my favorite villain of MLP: FiM. While King Sombra was okay, we saw little of him and we couldn't really see him develop as a villain (Hissing "Crystals" doesn't make a character intricate). Tirek was too easy, just power, power, destroy, and more power. Discord has grown on me in later years, he's a great comedic relief while also having several good episodes of him in it. While we haven't seen much of Chrysalis in total, I think she's got great potential to become the ultimate villain. She's cruel, ruthless, and outright slaps away a hoof reached out to her in friendship. In the finale she promised revenge while flying away. What will she do? Make a new hive? Go on a hunt for magical artifacts? Look for allies among other hives (If there are other hives)? I don't know, but I doubt we've seen the last of her.

Spoilers over.