History Recap / AvatarTheLastAirbenderTheLibrary

* SadisticChoice: Toph has to choose between saving Appa from the sandbenders or stopping the library from sinking with the rest of the Gaang inside.
** Although it's not really a "choice". She's ''blind'' in the sand, and her few attempts to attack the sandbenders are unaimed and don't hit anything. If she'd chosen to try to save Appa, she'd have failed, ''and'' the Gaang would've been buried with the library.

* OneWingedAngel: Wan Shi Tong intially looks like a regular owl when they meet him. But when he finds out what the group are doing, his form becomes much more larger and menacing.

* HeyItsThatVoice!: The professor is [[VideoGame/KnightsOfTheOldRepublic Carth Onasi]]/[[Franchise/MassEffect Kaidan Alenko]]. And Wan Shi Tong is Hector Elizondo.

* MidSeasonTwist: There will be a solar eclipse in a few moth that will depower the Firebenders.

* {{Foreshadowing}}: The chanting that plays while Aang is looking at the lion turtle scroll is the same chanting that is heard at the appearance of the mysterious island in the series finale.

** In the following series, Legend of Korra, we find out his ultimate fate. He died.

* ContinuityCreep: Season one was largely standalone episodes with a few minor ongoing plot threads. Season two introduced more continuity, until this episode begins a much tighter story arc that lasts the rest of the season.

* MidSeasonTwist: Literally in the middle of the season.

* AbnormalLimbRotationRange: Wan Shi Tong.

* DownerEnding: The Gaang are in the middle of the desert with no supplies, no transportation, and no way to find the kidnapped Appa.

* EarlyBirdCameo: Aang finds a scroll with a picture of a lion turtle on it.
** And, of course, the episode's titular Library showed up in Zhao's VillainRant at the end of last season.

* OwlBeDamned[=/=]TheOwlKnowingOne: Wan Shi Tong switches from the latter to the former when he finds out that the Gaang is planning on using the information they gained to invade the Fire Nation.

* MidSeasonWhamEpisode: Literally in the middle of the season.

* HeyItsThatVoice!: The professor is [[KnightsOfTheOldRepublic Carth Onasi]]/[[MassEffect Kaidan Alenko]]. And Wan Shi Tong is Hector Elizondo.

* HeyItsThatVoice!: The professor is [[KnightsOfTheOldRepublic Carth Onasi]]/[[MassEffect Kaidan Alenko]].

* AbnormalLimbRotationRange: Wan Shi Tong
* AncientKeeper: Wan Shi Tong

* HeyItsThatVoice!: The professor is [[KnightsOfTheOldRepublic Carth Onasi]]/[[MassEffect Kaidan Alenko]]

* UnusualEuphemism: "I've been training my arrow off."

** Although it's not really a "choice". She's ''blind'' in the sand, and her few attempts to attack the sandbenders are unaimed and don't hit anything. If she'd chosen to try to save Appa, she'd have failed, ''and'' the Gaang would've been buried with the library.

* OneWingAngel: Wan Shi Tong intially looks like a regular owl when they meet him. But when he finds out what the group are doing, his form becomes much more larger and menacing.

Each of the Gaang gets to pick a location for a mini-vacation. Aang's choice, the Misty Palms Oasis, is somewhat less cool than it was a hundred years ago, but they do meet a traveling historian, Professor Zei (Raphael Sbarge), who recognizes Aang as an Air Nomad. He (the scholar) is trying to find a legendary library out in the desert, one reportedly run by the great knowledge spirit Wan Shi Tong. Because of the extensive flying necessary to find it, and the less-than-solid nature of sand as a medium, Toph is essentially reduced to total blindness; she spends most of the episode in the shade of the building, trading good-natured grumbling with Appa.