The introduction of the Selfish Agents who represent the Seven Deadly Sins. The Selfish Trio are the first ones who were introduced. Ira who represents the third vice and Mamo who represents the third last vice are both introduced in Episode 1. Later, Bel who represents the middle vice is introduced alone. Then Leva who represents the second vice and Gula who represents the second last vice are both introduced in Episode 23.
Despite having a similar name, similar grades and even the same theme color and Elemental Power, Rikka is not alike Reika. Avoiding to make her an Expy, she's given a different background, resulting a different personality and different skills. While Reika was the over all most competent Cure of her team and was maybe the strongest Cure after Miyuki, Rikka is definitely not the strongest and is given a supporting role in combat. The Yamato NadeshikoOjou role is given to Alice, but even here, she has not the same role as Reika or Itsuki or Karen. Because the producer has given Alice a background that gives a reason for her passive role, she's not that strong/competent as Reika or Itsuki before Alice's Character Development and she's not as strict as Karen who hasn't friends in her childhood like Alice.
Cure Ace curb-stomping Regina makes sense, as she has to defeat her within five minutes before de-transforming. And her request to the other Cures becoming stronger is justified since villains as Leva and Gula summon Jikochuus who are more troublesome than Regina. And Ace lost to the Selfish Kingdom once, so she knows there are/were much stronger villains/threats than Regina.
The last part has become contradictory in recent episodes. Ace's past has becomes more mysterious.
The villains and the Monsters of the Week are known as Jikochuu, not only because they are selfish, Leva and Gula proves that they can become Jikochuu monsters. Both of them fuse together to become a monster. They also state that is their true power.
At first, many fans believed that Cure Ace's true identity was Marie Ange, due to their very similar appearances. Cure Ace is Marie Ange, sort of.
Cure Diamond's ice affinity. Rikka always likened herself to the Swallow from The Happy Prince. In the original version of said tale, The Swallow was frozen to death. It's a Fridge Irony, in a sense.
Why is Nikaidou seem to be the "leader" of Mana's Muggle friends? He's number 2, duh.
In Episode 45, we find out the frozen Marie-Ange was a decoy. How is it that the girls are still able to communicate with her through the Lovies? The Lovies are given by Ai, who we find out is Marie-Ange's body. Ai has been the one communicating to them all this time.
Why does Ai love chewing on Lance's ears of all things? It apparently may be a habit that runs in the family as King Jikochuu chews on the Giant Lance's ears in the same fashion as Ai does, and Ai is a part of Marie-Ange, the king's daughter.
Episode 26 showed the exact seat positions of Mana's class. Notice how all the named students (including the Cures) sit next to each other?◊ It's later revealed that Nikaidou, Momota, and Yashima are Mana's Childhood Friends, whereas Juujou and Mimura are members of Student Council. They sit next to each other because they're just that close.
In spite of being a Bigger Bad, Proto-Jikochuu came off pretty weak. Why? Because he's Proto-Jikochuu. You know how in-development, and therefore incomplete things often have "proto" prefix? Yep.
Cure Ace is all about five: the fifth Cure, has five types of Ace Shot, needs five Royal Crystals to transform, can transform for only five minutes, properly introduced herself in Episode 23 (2+3=5), gains her Magical Lovely Pad attack in Episode 32 (again, 3+2=5), her true nature is revealed in Episode 45, and she introduces the Five Vows of Pretty Cure. Not to mention her given name, "Aguri", is composed of five alphabets.
Jun wanted to be like Mana, but he chose to take care of the flowers because it fits him more. Come the final episode, and now he is the Student Council President...just like Mana. In other words, he gets what he wished for, only in different way than what he thought.
How does Aguri know about Melan and the Three Sacred Treasures? She got her memories from Marie-Ange, who definitely knows about them.
Episode two features a Jikochuu made from a traffic signal that can literally "stop" people, turning them into statues. Okay so far, but when he turns Cure Heart and Rikka into statues, we soon realize that they're still aware and conscious. This Jikochuu had turned an entire street and a courtyard full of people into statues...And I Must Scream?
The first episode title refers to Cure Sword as the last Pretty Cure. Does that mean the others are dead?
If you mean the last of the Trump Kingdom, then it's quite likely. If you mean the last overall, then obviously no.
Judging by the flashbacks in episode 7, Cure Sword was the Trump Kingdom's sole Pretty Cure, so the former is much more likely.
Aaaaand now it has been confirmed that yes, there were other Pretty Cure besides Sword, but every single one of them died trying to protect Trump Kingdom when it was attacked in the first episode. (No, really, the dialogue says they lost their lives.) Holy crap.
Gula attacks Cure Diamond, but Cure Rosetta protects her with Rosetta Reflection. That doesn't stop him and he eats the shield. Imagine what happened if he ate Cure Diamond...
It also looks like that he has eaten people before. He also tries to eat Aguri's grandmother in Episode 27.
In episode 41, the Cures are shown to be able to fly high above the Earth's atmosphere while transformed, using their new wings. Presumably their Cure forms grant them protection from the lack of atmosphere. However, the Fridge Horror involves Cure Ace, who can only be transformed for five minutes. What would have happened if the battle in space had taken too long and she lost her transformation right there?!
In Episode 47, King Jikochuu uses the mother of all laser beams to take down nearly the entire top half of the Clover Tower. Considering there are still people in Oogai Town, what's not to say that there were still people inside the tower? And I Must Scream?
Moreover, the place the tower crashed on may (or may not) have had buildings that also had people in them as well.
When Alice and the others are six years old, Sebastian gave Rikka something that looked like a tablet, despite it was probably 2005. And Rikka knew how to use it and she analyzed Alice's whole mansion with it. It's improbable that Rikka was that intelligent.
Considering Jonathan was engaged to Marie Ange and that Aguri, Regina and Ai are all pieces of the princess, does that mean one or more of them will fall in love with him when they grow up?
Out of the three parts of the princess, Ai has the most of Ange's spirit. It's technically the closest thing.
Regina is disarmed of the Miracle Dragon Glaive in episode 48, and is never seen again until the next episode. Considering the spear was still inside King Jikochuu when he disappeared, how the heck did she get it back?
Episode 47: Jun, Nikaidou, Momota, and Softball club members went outside to help panicking citizens evacuate, and the rest of the school were clearly shown evacuating. So why did they return to the school again in the next episode?