Princess Luna finds herself in a box. How or why, she doesn't know. All she knows, is that it's cramped and uncomfortable. Oh and there's this human thing that knows her but won't tell her how. At least until Saturday.
Thorax made it. He reached the Crystal Empire and convinced everypony he was a completely harmless changeling, who was just looking for some love and friendship. Just keep that cover story and—"We-he-hell, there's an explanation for that, Spike."
Celestia decided to visit an old acquaintance over tea and cake. Problem was, he was in Tartarus and on rehab. And he might or might not have a few hard feelings. And exceptionally-well repressed rage. All the more reason for check up, no?
When Cadance and Luna realized they shipped Celestia differently, there was only one way to settle their differences. Unfortunately for Spike, he was a living weapon of mass destruction in their shipping war.