While it's Played for Laughs, in "Quarreler's Pass", Anne's reaction to Hop Pop's questions about her having a boyfriend got some fans thinking about why she reacted that way: Is she embarrassed at being asked about it? Is she just annoyed at Hop Pop for invading into her personal life? Did it remind her of her own unpleasant (platonic or otherwise) relationships? Or perhaps, she isn't straight and feels insulted that Hop Pop assumed her significant other would necessarily be a guy just because she's a girl, but doesn't want to confess it yet, at least not until she's able to calm down? Does she simply refuse to answer the question, dodging it with a kick?
Despite seeing Marcy get stabbed by King Andrias, Anne insists that she is alive. Although Anne does turn out to be correct, is Anne somehow really aware that Marcy is alive, or is she simply in denial that Marcy may be dead?
Sasha dropping herself from Toad Tower. Was it really a Heroic Sacrifice to save Anne and the Plantars, was she temporarily Driven to Suicide over having lost her friendship with Anne, or was it both? In season 2, she seems intent on killing (or at least hurting) Anne and the Plantars rather than making amends with them.
Is Sasha truly angry at Anne for standing up to her, or is she actually angry at herself for letting things escalate the way they did? Toadcatcher hints that it's both.
Sasha's plans for Anne in season 2 are sinisterly vague. She is shown to hold a grudge over the fight at Toad Tower, and is clearly not intent on apologizing and making up. Does she want to defeat Anne in a duel to regain her pride? Force Anne to apologize for betraying her? Or does she have something more lethal in mind for either Anne, the Plantars or both?
How close were Sasha and Marcy? While Sasha does have her arm slung over Marcy in their BFF photo and Marcy does want to go back home with Sasha, it could be just her posing for the photo and Marcy just being a Nice Girl respectively. In the "Marcy at the Gates" flashback, Sasha seems rather apathetic to Marcy's clumsiness, content to lean back and snark while Anne frantically warns Marcy about things she's about to crash into.
In "Froggy Little Christmas", we can see Anne writing two separate letters to Sasha's parents, in contrast to the one letter for Marcy's family, suggesting that Sasha's parents are divorced. Many fans think that Sasha's Control Freak tendencies originate from this possible fact; unable to control her home life involving her parents' separation, she fulfills her need for control through Anne and Marcy.
With the confirmation in the series finale and Braly on Twitter that Sasha is bisexual, the Les Yay moments with Anne and Marcy can be read as not simply unintentional subtext, but Sasha having unconscious underlying romantic feelings for her best friends, especially when it comes to Anne.
Marcy Wu
Marcy has been subject to this since her debut. Anne reveals, and Sprig finds out, that Marcy wasn't a Beta Bitch to Sasha's alpha, and instead was an Endearingly Dorky Nerd that had no survival skills until she came to Amphibia. At least, we have Anne's word and flashbacks for it, but she knows that Marcy was encouraging her to shoplift the box, since Marcy liked the jewels. Was Marcy secretly tempted to be as reckless as Sasha was, or was she giving in to Sasha's peer pressure and Toxic Friend Influence? Or rather, why didn't she shoplift the box herself, if it was that pretty to her and was interested in it first? Is Sprig right to be a little suspicious? For now, it's up to the audience.
In "A Day At The Aquarium", near the end of the episode, Marcy reaches a hand out to a sad Anne, only to back out immediately and instead tell her to "follow her heart" with the Plantars. Before she changed her mind, was Marcy going to comfort Anne about being separated from the Plantars, or was she simply just going to hug her? What exactly was going through her head that caused her not to reach out to Anne? What was she even planning on saying in the first place?
A lot during the season two finale (spoilers are marked):
Is Marcy truly that oblivious to the fact that neither Anne nor Sasha would have willingly agreed to leave their families to go on magical adventures? Anne's flashbacks reveal that on Earth, she had the survival instincts of a broom. Did she forget that it was Anne's birthday? (It's likely, given that she kept her heads in her RPG books).
In regards to the structure of the trio's friendship, was Marcy willingly oblivious to how toxic it was because she had no other friends? Anne and Sasha seem to have had other people, but Marcy was alone with only the two of them.
Did Marcy ever feel remorse for stranding her friends in Amphibia? If so, did it influence her into becoming the Nice Girl she is to make up for her mistake?
Why didn't she tell the truth to Anne, Sasha, or even Sprig? Sprig forgave her for what she did to Anne, understanding that Marcy didn't want to hurt anyone, not even Sasha. Anne thinks that it's her duty to protect Marcy from the world, not the other way around, and she has forgiven her friends and family for worse oversights. Did Marcy have an inkling that lying to her friends wouldn't go over well, or was she in denial that they could keep having adventures?
In the end, it's unclear who is to blame for Anne shoplifting the Calamity Box and stranding the girls. On the one hand, Anne should have had the guts to stand up to her friends, say no, and go to her birthday party, something that Anne acknowledges with hindsight. Yet Sasha is the one who bullied Anne into doing it, not caring that Anne's family was waiting to celebrate her birthday. It's revealed that Marcy either forgot or didn't care that it was Anne's birthday, only thinking about using the box to travel to another world as soon as possible without considering the consequences or the ensuing trauma. What's more, it's likely that the girls could have pooled their money to buy the box legitimately, which would have made Anne more comfortable with it even if the timing was worse.
Additionally, it's possible that Marcy specifically told Sasha about the Calamity Box in order to take advantage of her controlling nature and ensure that Anne would steal it and put her plan into motion.
Is King Andrias truly a monstrous psychopath who cares not one bit for his subjects and is willing to commit immoral acts to succeed, or was he possibly corrupted by his Master, meaning that he should not be held accountable completely for his sins?
In "The Core and the King," we get a flashback to when the music box was stolen. At that time, he was still willing to invade and conquer other territories, but felt that wiping out species was going too far and had a genuine bond with his closest friends, who were a frog and toad. However, after Leif took the box and due to comments from his Abusive Dad, he decided to punish the entire frog species and became more cold-hearted. Thus, he was not fully corrupted, but he does or did have some moral compass, though it may have faded over time. How sympathetic he is varies from person to person after this reveal.
Why is Andrias keeping Marcy on life support, as the season 3 opener shows? Is she still useful for his plans to conquer the multiverse as one of the three humans who can charge the gems? Does he feel that she belongs to him given both of her best friends were horrified with what she did and refused to go with her plans? Or, despite himself, is Andrias more fond of Marcy than he admits, given she treated him as her mentor and has confided in him?
"Olivia and Yunan" implies that it was a combination of options 1 and 3: the Host demanded Marcy as a body, and she needed to be healthy enough to handle the possession. Andrias, however, had asked the host to choose someone else, despite Marcy turning on him, because he likes her and respects her mind; his master overrode him. That is, if we can believe him and he wasn't being his usual Bitch in Sheep's Clothing self to taunt her further just as the Core prepared to overwrite her mind. He did look away, however, when the process started and Marcy was screaming in agony.
Did Marcy genuinely beat Andrias at Flipwart, or did he deliberately lose in order for Marcy to trust him more? "True Colors" hints at the latter and "Olivia & Yunan" hints at the former.
Others
In "Maddie and Marcy", did Mr. Flour actually believe Maddie was going to kill her sisters, or was he simply joking when he told her to resurrect them after killing them?
Speaking of Mr. Flour, does he not care that Sprig and Maddie are no longer engaged? Or did he forget all about that?
Was Sprig lying when he said he doesn't remember how his mother looked like to avoid the trauma? Or is her death the only thing he remembers? While we do know that they died during Polly's early years (late enough for her to remember it too), the precise time gap between the two is unknown. Alternatively, he may have suppressed most of his memories of her because said memories may have affected him too.
The Mayor's reasons for his Hazy-Feel Turn in the season 1 finale where he rescues some of the frogs from the collapsing tower. He claims it's Pragmatic Villainy in that he needs constituents to embezzle, but he could have easily turned tail and no one would have noticed in the chaos. Is it Hypocritical Heartwarming that only he can torment his frogs? Mistreatment-Induced Betrayal since Grime included him among the citizens that would be punished for insubordination? Or a genuine Heel–Face Turn after Anne was gracious enough to ask for his help in "Anne of the Year"? It could also have to do with the fact that his embezzlement scheme was also him effectively stealing from the toads, who are unlikely to be as forgiving as Wartwood. There is the fact that when given a promotion, he asks Anne's help for sabotaging it rather than accepting it outright.
Mr. X seems to truly believe that he's stopping an alien invasion by investigating the Plantars and taking them into FBI custody. The way he treats Anne, though, hints that he may just be Lawful Stupid and a bit petty; he tries Tasering her when spotting her in a movie theater. She went missing a few months ago, and three girls vanishing would have made news in the area. Thus, he could have found out who she was with a bit of detective work. As the Boonchuys point out after the Plantars and Anne make it back to Amphibia, he could have simply asked the Boonchuys for the truth, and they would have cooperated. Could it simply be that he is a Conspiracy Theorist that hates admitting he is wrong, or does he have tunnel vision?
Because of how little we know about him, Barrel the Brave also falls under this. Could he have opened his heart and held onto the fond memories of his friendships like Leif did? Or did he, like Andrias, become bitter towards his former friends and perhaps even inspired the other toads to pick on the frogs over Leif's betrayal? note He was present when Andrias said that the frogs should be kept in line, right before being banished.
