Lena and Violet being paired with Huey and Louie respectively makes sense—their personalities are direct foils to each other. Huey is painfully rational and always tries to find the least violent solution, which turns out to be a lock for his savage side; in contrast, Lena wears her very illogical magic with pride and tends to go for the most violent solution, all of which are a cover for how vulnerable she feels. Likewise, Louie is a skilled liar who can sweet-talk his way out of anything, which is the direct opposite of honest, socially inept Violet. Both girls end up helping the boys see their inner strengths, which allow them to grow.
Dewey and Webby are also direct foils to each other in this episode. Dewey is very gung-ho and impulsive, which is contrasted by Webby's carefulness and strategic mindset. However, unlike the other two pairs, they have teamed up with each other before due to their Best Friend status and here, it's the male (Dewey) who helps the female (Webby) grow.
Dewey is able to get up to the top while he is blinded, but Webby struggles. Why is that? Because Dewey is extremely impulsive and a thrill seeker—he's been through dozens of scenarios where he's stuck in a strange place and has to escape it quickly, probably moreso than Webby. In contrast, Webby has spent her whole life inside of the manor and is new to adventuring. She might be confident in her abilities when she can assess the situation, but when put in an unfamiliar setting without her senses, she's understandably cautious.
Violet being a member of a "Spice of the Month" club explains how she so easily identified all three spices on sight earlier on.
Why were the thugs more impressed with Louie's real feats? On top of his already stated feats, they are dealing with a person who became the richest duck in the world at a young age.
It seems unusual for F.O.W.L. to have four of their top agents on the mission to steal one of the Missing Mysteries, especially considering they've shown the ability to steal them with minimal resources just fine before. But stealing the sword wasn't their goal this time. They sent all of those agents to fool Scrooge into thinking they were definitely after the treasure instead of being up to something else.
This works doubly well because Scrooge now knows that they're after the Missing Mysteries. Scrooge didn't know they were after the Missing Mysteries until last episode despite knowing F.O.W.L. was after them. This gives the impression that they're starting to get desperate so when Scrooge gets the sword he thinks he's gotten one over on them while staying unaware that he's just been played again.
Note that it's also possible the Phantom Blot would have rendered the sword WORTHLESS...since he would also have sucked out the magic making it powerful...and that this is a perfect example of an ALMOST perfect Xanatos Gambit, and a perfect Kansas City Shuffle. Basically? If they get the sword without resistance, they have a powerful magical artifact. If they get the sword with resistance? It's child's play to grab Scrooge at some point. If they fail to get the sword with resistance? Still easy to get a feather. And if they fail to get the sword because the Ducks were there early? They can try again with a sword.
This would also explain how Huey was able to beat Steelbeak, who fought and won against Darkwing last episode, on his own. While part of it was definitely Huey taking him by surprise it's highly unlikely that Huey could have actually won on his own... unless Steelbeak wasn't actually supposed to win.
It might seem unlikely that Steelbeak would go along with losing a fight to a child, and one who's not an especially gifted fighter at that, given his pride. But remember the last time he went his own way on a plan. Bradford probably drove it in with steel spikes that Steelbeak better stay on task this time.
Steelbeak would likely be on board with deliberately losing to Huey because it would ultimately let him be part of getting one over on Scrooge. Outwitting Scrooge, one of the smartest and sharpest men in the world, would appeal to Steelbeak given his lofty opinion of himself. He'd be more than happy to take a dive if it was meant to fool someone like that.
Apparently, the Fountain of Youth cannot repair damaged tissue or scars, which is shown with not only Rockerduck’s taste buds still being damaged even after having his youth restored, but also with Jeeves still having his skin in pieces and stitched together even if he’s regressed to a baby.
For a second episode in a row, Launchpad is nowhere to be seen in it. If Istanbull is in the same location of the Earth as its real-world counterpart, Istanbul, it would be roughly halfway around the world from the Pacific Coast, so daytime there would be nighttime in the Duckburg/Saint Canard area. This is supported by the fact that Violet and Lena were in the middle of a sleepover when Scrooge ordered everyone on the plane. Once again, Launchpad is spending the night in Saint Canard with Darkwing and Gosalyn.
Looking back at "The Last Adventure!", Black Heron didn't explicitly say she grabbed Scrooge's feather. She was just shown grabbing a feather saying "we got what we came here for". Many people had assumed she grabbed Scrooge's because she was fighting directly with him while the others were distracted - but looking at a glance, she also whacks all of the kids with her mechanical arm, giving her an opportunity to specifically grab Webby's feather as well - which was done before the opening even started.
Darkly humorous, as he is a German shepherd—after all, dogs typically do hate cats, plus there's a small smackerel of Fantastic Racism in play.
Fridge Logic:
Dewey, who had encountered Steelbeak alongside Launchpad, was with everyone when the group assembled to take the sword collectively from everyone (even saying that "their Bazaar Adventure was over"). Launchpad in "The Last Adventure" recognized Steelbeak as "that video game boss" but why didn't Dewey recognize Steelbeak, who outright kidnapped him, as "that one boss". Just seems a bit off.
In the previous episode Darkwing Duck told Scrooge that someone with a steel beak tried took the Solego Circuit. Is possibile that off screen Dewey remembered that "boss" and realize that he has to be real and part of F.O.W.L, so he wasn't surprised to meeting him. Notice that Huey know who he was despite only Dewey had met him, and he would have no reason tk mention him if he didn't know he was real. Launchpad wasn't there when Darkwing called, so he doesn't know about him (and even if Drake told him, he isn't brighi enough to put two and two together)
