Sokka forges his own sword from a meteorite in this episode. Because of this it has a black look and is much stronger than other metals.
A few of Sokka's qualities which aid the gang in their travels are revealed in this episode, such as he is the only one who can read maps and make good scheduling.
Earthbenders can apparently bend earth from outer space.
Toph states that her earthbending masters were badger moles. Previously in the DVD commentary for "The Blind Bandit" the creators stated that this had always been the case, and that they had been looking for a way to put it in the show.
At the end of the episode Piando gives Sokka a White Lotus Pai Sho tile. Implying that he is a member of the secret Order of the White Lotus group, as is Iroh, as seen in "The Desert
Weapons in the weapon shop include a ball and chain, a guandao, a mace, a naginata, nunchucks, a sai, and jians.
The gang eats "Smoked Sea Slugs", apparently a common food in the Fire Nation.
This is the first episode of the series whose main plot is focused mainly on Sokka.
If you look closely over Piando while he is presenting the sword to Sokka you can see White Lotus designs above the door.
Piando: As we trained, it wasn't your skills that impressed me. No, it certainly wasn't your skills.
Piando: You showed something beyond that. Creativity, versatility, intelligence. These are the traits that define a great swordsman, and these are the traits that define you.
Aang: What should we do today?
Toph: I'm tapped out. I already picked my toes...twice.
Toph: The first time's for cleaning, but the second time's just for the sweet picking sensation
Katara: Why would you agree to train someone from the water tribe?
Piandao: The way of the sword doesn't belong to any one nation. Knowledge of the arts belongs to us all.
Toph: I miss Sokka.
Katara: (trying to be funny) If you miss him so much, why don't you marry him?
Aang: Guess good jokes don't run in the family.
Katara: Everyone's a critic.
Piando: You're going to need a better Fire Nation name than that. Try Lee. There's a million Lee's.
Escape from Alcatraz
The scenes where Iroh works out non-stop in his cell is an allusion to the movie Escape from Alcatraz in which Clint Eastwood's character works out non-stop in his cell in order to get into the best shape he's ever been in.
Mastering calligraphy, rock sculptures and landscape paintings are also all things a master swordsman would have had to have mastered in feudal Japan.