>Twilight complaining that her princesshood just isn't princessly enough
Hopeful Side: Maybe they'll redeem themselves by demoting her and letting her pursue a more realistic career path!
Cynical Side: Don't be stupid, Hopeful Side. This is where she ascends to godhood above everyone else.
>"Princess Luna raises the moon, Princess Celestia raises the sun, and Princess Cadence…uh…what does she do anyway?"
"Sells pink princess toys, just like you. Let's sing about it."
Uh, I think you're on the wrong set, Rafiki.
Wait, Princess Discord? Oh you sneaky fuckers. I walked right into that one.
I'VE GOT IT! While absorbing the pegasi's flight he accidentally a whole Derpy. Unable to handle the sheer, raw derpiness, he's defeated while derping derpily. Twilicorn is stripped of her specialness and banished back to the library and a new bubblebutted princess arises for having saved everypony. No? Oh well. Probably something bland like Discord was only pretending all along to be on Tirek's side.
>Tia: We must all dump our magic into you Twilight.
>Twilight: But why me?
Cadence: Because you're even more useless and expendable than I am.
So, uh…since Discord has this innate ability to detect magic, sensitive enough to use it to find Tirek, he surely won't notice that subtle blip of three alicorns Heimliching out their powers, right? …yup, called it.
>Fluttershy: Discord! Curse your sudden but inevitable betrayal!
>Discord: Ha ha ha! Mine is an evil lau–wait, et tu Tirek? Ah, curse your sudden but inevitable betrayal!
OK, so Discord wasn't being a mole after all. Can't call 'em all.
TWILIGHT uses ANNOY! It's not very effective.
TIREK uses BARGAIN! Oy vey, what a deal!
Gratuitous effects! Oh and btw, buy more toys.
Tirek: What a world, what a world…
Oh for fuck's…Miracle-Gro castles now?
>Twilight: And I couldn't have done it without all of you!
I get to be a fucking alicorn princess with a castle and a title. All of you whom I couldn't have done this without? You get chairs.
I still dislike the direction the show took with alicorns everywhere. But on the whole, given that we're stuck with Twilicorn (and Cadence) now, this episode did a decent job of working with the story as it stands. We have an unredeemed villain–and one who actually is unmistakably a villain this time*. We got some advancement on the world and, well, one character anyway (maybe two, we'll see how Discord is handled next season). So even though I would've preferred the show to have progressed with only the original two alicorns and less Hasbro meddling, I'd say this season finale was on par with S02's, which was pretty damn good if you overlooked the way it trashed the story up 'til then.
*No, Sombra doesn't count. He wanted to what, erect dark crystals? Being a Jim Henson fan is evil? Could he possibly have been more ambiguous a "villain?"