The Storm is a defining event for the kids, particularly Yi Lin and Tseng.
One day, the Blue Flame is passing through the seas near the northern Earth Kingdom. As they continue, dark clouds begin to dot the horizon, but despite Tseng's warnings, Hayoda chooses to continue straight forward instead of detouring their voyage. All too soon, the storm is upon them and tall waves smash against the vessel again and again.
Finally, the storm passes with the Blue Flame in mostly one piece. But with the new calm comes the terrible realization that Yi Lin is nowhere to be seen.
Tseng simply stares blankly towards the endless sea, not even moving or blinking, just standing there holding on to the rail, his grip getting tighter and tighter.
Hayoda: This isn't good, this is not good at all.
Irah, still not sure what to do, occupies her time by picking up the pieces of debris all over the ship. Yue, unable to contain herself any longer, starts crying, hugging her pet ocelot-raven, desperately seeking any comfort at all.
Hayoda feels the most guilty. He was, after all the supposed captain. It was ultimately his decision to continue with the same route, despite Tseng's warnings.
Hayoda: Listen, man. I'm sure she's alright. We'll find her, I promise you.
Tseng: Just like you promised that this route was safe?!
Hayoda: I'm sorry, I didn't know that--
Tseng: Yes, you didn't know! I did, but you didn't listen to me, did you?!
Hayoda: Calm down, it's going to be alright.
Tseng: Don't you understand?! My sister is dead!
(finish this up)
"If we need more Tseng stuff, then maybe we should consider working on the whole MY SISTER IS DEEEAD angle during Yi Lin's adventure. Maybe after she disappeared the whole "I was supposed to protect her and now she's GONE" opens up a reservour of impulsive kickassery, leading him to basically take over the ship in search of his sister. Between the scenes with Yi Lin and Niriku, it cuts to him busting into taverns looking for information, pulling all sorts of crazy stuff like water tentacles and ice spikes. Then when he finds her he goes back to normal (after a quick cry)."
"Needs to be filled with awesome, frightening displays of RAGE, and glimpses of the true extent of his waterbending. He IS Katara's son, and a force not to mess around with."
"Tseng considers himself the responsible one of the group, so he'd be a mix of Serpent's Pass Aang and Southern Raiders Katara- stomping on everything in his way, trying to do all the fighting himself, and outright hostile to everyone who asks. This goes on for a while until it culminates in them finding, say, a scrap of Yi Lin's clothing in the possession of some pirates who were planning (idiots) to blackmail the Avatar with it. Tseng goes hyperrage on them and very nearly kills their leader only to be stopped by Hayoda, and then he just has a MASSIVE breakdown right there. After that he's like The Drill/Ba Sing Se Aang- determined to find Yi Lin but not so determined as to let it change who he is."
"If anything, Tseng should just snap at every little thing that goes wrong, even in the slightest."
Hayoda: "I don't think this is the right way. Maybe we should have taken a left back there...?"
Tseng: "OH GREAT! NOW WE'RE LOST! NICE GOING, HAYODA! THIS IS JUST PERFECT!"
Hayoda: "Well, I talked to the fishermen at the dock. They hadn't seen anything either..."
Tseng: "Oh well, that figures, doesn't it?! We'll just chalk this up to even MORE time wasted! I've got an idea! How about we don't even TALK to the next group! How about we just sit here and twiddle our thumbs! There's an idea! WE'D GET THE SAME AMOUNT OF WORK DONE!"
"At first, the other three put up with it because they understand that Tseng's frustrated and angry. But eventually, Hayoda has to Motivational Punch him because he's taking it too far."
"Yeah, at first he's just sarcastic and on edge. But eventually it starts building to the point where the only way he communicates is by screaming insults at his friends. And it's when he starts tearing into Yue that Hayoda belts him. And by the time he stands up, Hayoda grabs him by the shirt collar and pins him against a wall."
Hayoda: "I'VE HAD ENOUGH OUT OF YOU! What is WRONG with you?! You've been getting worse and worse! I will NOT have you INSULTING US every step of the way! YOU'RE SUPPOSED TO BE CALM! COLLECTED! WHAT HAPPENED TO THAT?!"
Tseng: "..."
Hayoda: "What's wrong with you?! I get that you're worried, but this is too much! You know she's alive, right? You know how tough she is! Right? RIGHT?!"
Tseng: "..."
Hayoda: "ANSWER ME!"
Tseng: "... Yeah..."
Hayoda: "THEN KNOCK OFF THE ATTITUDE!"
(Tseng pushes Hayoda away.)
Tseng: "You don't understand at all! You don't know what it's like to worry about your sister like-"
(*WHAM!* Hayoda punches him again.)
Hayoda: "Don't you EVER say that to me! DON'T YOU EVER ACT LIKE I DON'T CARE ABOUT YUE THE SAME WAY YOU CARE ABOUT YI LIN! NOW LISTEN TO ME! We WILL find her. I stake my LIFE on it. I don't care how long it takes, I don't care what I have to DO, but we WILL get her back. IF and only IF you can manage to calm down. Because if you can't do that... Then we'll say our goodbyes here."
(There's a long pause as Tseng and Hayoda glare at each other. Tseng deflates. He slumps his shoulders and puts his head down.)
Tseng: "...I'm sorry."
Hayoda: "It's okay. We're all in the same boat, buddy."
Tseng: "It's just... This... We've never really been... apart. Like this. I mean, Dad would... take her on trips and I'd stay home but... This is..."
Hayoda: "We know, man. We know."
Tseng: "I don't know where she is. I know she's alive. I know she's probably safe. I mean, knowing her, she's probably made a..." Tseng laughs uneasily. "Made a new friend and they're joking around, having fun."
Hayoda: (Smiles at him.) "Yeah, she probably is."
Tseng: "Hayoda. I'm sorry. I've said some pretty mean things recently, and... That thing I said about you and Yue. I didn't mean it."
Hayoda: (Hugs him.) "I know you didn't." They separate. Hayoda grabs Tseng's shoulder and shakes him. "Now come on. Wipe the tears from your eyes and the snot from your nose. We got an Airbender to find."