"Bolin, do the thing!"
Not entirely a dramatic confrontation, "The Battle of Zaofu" pairs up Varrick and Bolin as Bataar Jr observes Varrick's work to weaponize the spirit vines. Varrick is pretty smart and great at hiding his plans under his eccentricities, so it doesn't take much to ensure Bolin stays by his side.
They're a hilarious duo, as they've been in the past. Varrick keeps using his trademark, "Do the thing," and Bolin, of course, never has any idea what "the thing" is. Where Meelo's lines quickly become groan-inducing, Varrick, Bolin, and maybe even Zhu Li could probably make their own series work.
Varrick does the whole "build a bomb to negotiate my freedom" thing while working on the spirit vines, and it works to get rid of Bataar and all the Earth Empire guards. Knowing Varrick's technical genius but emotional immaturity, it's hard to tell if he's actually built a bomb or was bluffing. At least, until he tells Bolin they've "had a good run." Bolin's not too shabby under pressure lately, and manages to escape the blast with Varrick.
Bataar reports to Kuvira that Varrick and Bolin have died, but he thinks he can replicate Varrick's work with the help of Zhu Li. This seems like a perfect set-up for Zhu Li to wreak some havoc on Kuvira's plans, but honestly after her split from Varrick last episode, I'm not convinced which side she's on. It's possible his attitude after their tender moment was the last straw for her, but it's a question that will certainly be answered before the end of the series.
Judging by the comments on previous episodes, fans were a little disappointed that Korra's whole internal struggle seemed resolved by the removal of the poison. It was building up to be a fantastic arc but had no real answer for the emotional struggle. I shared that concern, so it's great to see that Korra's still dealing with emotional fallout from years of conflict and what appears to be a struggle with her own capacity for violence.
I mean, it's great as television. It's not so great for Korra and everyone she cares about as Zaofu falls to the Earth Empire, Suyin's family is mostly incarcerated, and Bataar Jr is now working to weaponize the spirit vines.
Bottom line: The first showdown between Kuvira and Korra is a fantastic fight, but the return of Shadow Korra is the biggest blow of the confrontation.
Recommendation: Definitely not an episode you can skip,"The Battle of Zaofu" is packed with excitement, jokes, and continuity.