<p>My favorite one is actually one that spans the entire series: "The Boy in the Iceberg" and "Avatar Aang" (actually with the prefix of Sozin's Comet Part 4, but that ruins the symmetry for me) both refer to Aang, obviously. But they also encapsulate his journey, because at the start of his show, he's a naĂŻve and goofy little kid, but by the end, he's a full-blown Avatar who you would be wise not to mess with.
</p><p>In The Legend of Korra, there is "Skeletons in the Closet", which of course refers to how Tarrlok and Amon are actually related, and "Endgame", which is what the final few moves in a game of chess are called when there are only a few pieces left on the board. Interestingly enough, "Kuvira's Gambit" also refers to chess. A gambit is an opening move, hoping to get an early lead on your opponent, which is what Kuvira does with the mecha suit and spirit cannon. "Long Live the Queen" has had its own discussion, but that's a phrase spoken when the monarch dies, and in another pleasing symmetry, "Korra Alone" is naturally a callback to "Zuko Alone", where their respective journeys were similar.
</p><p>I could go on here, but there are just too many to mention, so I'll leave it here.
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