So they've finally revealed the two-part season final which will have a villain in it. From what we know already, it's sounding to be an epic episode like ACW, let's just hope it meets my expectations.
Part 1: What we know
1.) There will be a new villain. (or, Celestia forbid, an old villain with an elaborate trick).
2.) This villain is so big a threat that apparently Discord couldn't defeat him/her, and it'll take the power of four alicorns.
3.) Discord will be in it. Celestia will send him after the villain instead of Twilight, and the villain will defeat him. (well, either that or...)
4.) Celestia, Luna, and Cadance transfer their powers to Twilight.
5.) As the title implies, Twilight is getting her own kingdom.
Part 2: Expectations and mysteries
1.) The villain. For over a year I've been waiting for another Chrysalis/Sombra. To be more precise: A villain that is an actual character rather than just some vines. A villain that is as dark as Chrysalis atleast. A villain with epic battles around him/her. And of course, a spectacular death scene like Sombra got. Again this has to be a powerful villain who poses a real threat it would be a bit of a letdown not to. The whole idea of a Twilight Spirit Bomb sounds promising...
Also who or what is this villain going to be? Will Chrysalis make a return? Probably not, Shining Armor and Cadance defeated her once already there's no way she'd pose this big a threat, besides comics aside she should be dead from that fall. G4 version of Tirek, maybe? Assuming G4 and G1 aren't in the same continuity because Tirek died in G1. Maybe Firefly naming the Wonderbolts in Testing, Testing, 1, 2, 3 is foreshadowing of that?
2.) Celestia, Luna, and Discord. So the villain defeats Discord, and Celestia, Luna, and Cadance transfer their powers to Twilight? I hope they don't get killed off. Celestia and Luna will probably survive, but will they lose their alicorn powers forever? (before you ask it was other "conspiracy theorists" who suggested it wouldn't end well for the alicorns) And what about Discord? Is he going to survive the battle with the villain? I hope so. What if he is the villain, in the shadows? Even if he gets an uber spectacular death scene I wouldn't be satisfied there because I wanted him to stay the "not-always-reliable ally". But I think others want him to return to the evil spirit of disharmony we knew and loved in Season 2. They can't please everypony. I was thoroughly satisfied with Sombra, but most of the others weren't.
3.) Twilight's kingdom. Is Twilight going to have to leave her friends to rule this kingdom? Is she going to become immortal, replace Celestia and Luna as rulers of Equestria, and outlive all her friends? They said she would neither leave nor outlive her friends, but did they change their minds? Maybe the kingdom is the Everfree Forest castle, because of Power Ponies
4.) Rainbow Power. If Twilight is going to destroy the villain with a Spirit Bomb created with alicorn magic, and get her own kingdom after, where does the mystery box and the Rainbow Power come in? Does the Rainbow Power provide the next protection for Equestria as quicker and easier than the Spirit Bomb? Will it be something else entirely? Is it even going to be Rainbow Power? Is the villain what's really inside the box (in which case, why would the Mane 6 be demonstrating their Elements to get items to release him/her?)? Will it be held off until Season 5? Or will the Spirit Bomb fail (like when Goku used it on Frieza) and then the Mane 6 get the Rainbow Power soon after?
Anyway, Imperfect, here is their chance to top themselves. If they disappoint, I lose all faith in the two-parters from here forward. It sounds awesome already, but we'll have to wait and see.
Edit, April 27th: I think the villain might be an entity similar to Galactus based on being the "biggest" threat, and all the comic references, as well as lack of ability to come up with two-parter villains who speak. (even Sombra had lines) And one thing my pinkie sense is telling me is that somepony with hooves and a horn is going to die this episode.
Part 3: Review
Well I'll say it was my favorite episode of the season now, beating out Princess Twilight Sparkle which was only for Discord's role and the epic battle of Nightmare Moon and Celestia.
First, the villain. I suspected if there was going to be a new villain since they seem unable to come up with new ones anymore, Sombra and (in a sense) Nightmare Moon are dead, Discord reformed, Chrysalis presumed dead (and at risk of her character being ruined if she returns), the best they could do is a Tirek return seeing as how he was the darkest (and IMO the coolest) villain of G1, though I wasn't 100% sure they would but it was awesome to see Tirek in G4, and I notice they changed him much from G1, and if anything they made him darker. He doesn't quite have the same creepy vibe of Chrysalis and Sombra (aside from his first scene) but everything I said above (and below regarding the battle) still stands.
Second, Discord. So he betrays the ponies which I hoped he wouldn't, but apparently had a tough time deciding between Tirek and Fluttershy before he gave in to Tirek's manipulation. But he learns the true magic of friendship and is 100% reformed now, he gives Twilight her key as I was hoping he would (much better than Rock Father made it sound because he never mentioned the Discord thing) and I don't think even Rainbow Dash hates him anymore.
Third, the epic battle. This is more epic than the fights with Chrysalis, the changelings, Sombra, Demon Sunset, and Celestia vs. Nightmare Moon put together. It had a Dragonball Z vibe to it. Let's see the non-believers argue with this scene! (although apparently the fandom is becoming more known since Jeopardy has questions about MLP now) Because of the battle I was almost tempted to put Tirek above Discord as my favorite villain. Also the Mane 6 make Tirek taste the rainbow. Although I did feel mild disappointment at first they just sent him back to Tartarus instead of destroying him, I'm not too disappointed since I got what I wanted with Chrysalis and Sombra. (Inspiration Manifestation as good as confirms Chrysalis is dead)
Fourth, the princesses survive and so does Discord. Rock Father and imdb, respectively, had me concerned about them (not that I 100% believed Rock Father, even though what he said turned out to be true). Of course they wouldn't kill Luna, the fandom would riot if they did.
Fifth, Luna sings. And all three princesses sing at once. Also, as of this episode, Luna has appeared in 6 episodes this season, breaking her Season 3 record of 4.