Skooled! is probably my favorite episode in this part of the season, I wasn't really expecting anything so seeing Heinous suddenly come back as a cool, competent and interesting villain and just tear through everyone was really hype. It's also cool to see St. Olga's slowly developing as a setting and subcast, Princess Arms becoming their leader and organizing the princesses into something respectable was nice to see and she's a neat character too.
It's a shame Meteora derailed so hard but it was really exciting at the time. I hope we at least see a little more of St. Olga's. Best single moment was Heinous tearing out Pony Head's horn, even though it was offscreen.>3a
The Jarco breakup in Sophomore Slump was really well done, the atmosphere is gorgeous and Jackie got the best possible send-off she could have hoped for. Marco got what was coming to him in a way that was deserved but not mean-spirited. Jackie's characterization was excellent, both with how maturely she handled it and how you could see it was still hurting her to cut him loose, especially after Marco hit her with that brutal line.>Battle For Mewni
Everything from Star realizing she has to use the Whispering Spell to her resurrection is pure kino. It has some of the coolest scenes in the show with Goo Toffee towering over Star and some really raw emotional scenes both times that Moon fears her daughter is dead. Definitely the peak of the season, which is a shame because it's basically the beginning, but it's better viewed as the end of what came before anyway.