Anti-Climax Boss: After spending most of the series as a shadowy mastermind who was pretty much behind everything, Kalandre is killed not only incredibly easily, but also by a supporting character, and by accident. Then again, the rest of the book provides a (arguably) very satisfying climax.
Base-Breaking Character: When Tenebris joined the protagonists, fandom got really, REALLY divided. Some enjoyed her presence as a new protagonist, others loved to hate her. Seems the situation has changed, though.
Broken Base: The ending of volume 18 is also a notable offender. Is it a perfectly satisfying, albeit odd climax ? Or is it an abysmally crappy ending that can't even be called as such ? The fandom got REALLY divided on the matter as well.
Complete Monster: Anathos is an Omnicidal Maniac with absolutely no code of honor. Imprisonned in the Bearer by his kind for destroying the original planet of Alysia, Anathos seeks to free himself by manipulating the elf Shimy into receiving his mark so that he could use her as his host. When the Legendaries prevent him from using Shimy, he takes possession of Danael before crushing and savagely crippling the protagonists and mocking Jadina about her relationship with the now-"deceased" Danael. After killing Elysio, Darkhell and the Guardian who tried to stop him, he leads a rampage with his Hellions across the world to annihilate humanity by wiping out the major cities, sicking the Vulturs on the survivors and creating a plague to exterminate people he wouldn't bother killing himself. He orders his Hellions to physically and mentally torture Tenebris for information, and when his Dark Mistress Dark Jadina begs him forgiveness for failing to kill the original Jadina, he blows her head off just after pretending to forgive her. Humiliated by the Legendaries, he attempts one last time to destroy Alysia before Kalandre stops him.
Curiously, Dark-Gryf seems to have gained some popularity as well.
Evil Is Cool: Anathos is surprisingly popular amongst the fans despite, or rather precisely because he is the evilest character in the whole serie. Darkhell gets it as well to an extent.
While opinions concerning Skroa's status as a villain are mixed, everyone agrees that his design is pretty cool.
Evil Is Sexy: Tenebris in her adult form. The opinions may vary concerning her child form;
Conversely, Darkhell isn't exactly beautiful as an adult, but his child form is handsome in its own right. And his Fusion Dance in the Anathos Cycle makes a hint that he might have once been a quite good-looking Bishōnen.
Invidia and Kasino in Origins.
Fan-Preferred Couple: Danael/Shimy seems suprisingly popular amongst fans. So does Shimy/Anathos, no matter how few sense it'd make. By volume 18, the former seems to have become canon. We think.
Both Shun-Day and Shimy get embarrassed respectively when Gryf accidentally puts his hands under her top and when Jadina steals the top of her swimsuit. If you consider the fact they are both trapped in 12 years old bodies, and as such possess no breast, it seems kinda weird to see them having such a reaction... While this looks like Fridge Logic at first, this actually finds a solution as Fridge Brilliance. Even if the characters are all 12 years old now, all the major protagoniss were adults before the curse struck Elysia. To the girls, no matter their physical age, they're still adults in mind. They might not have cared about this when they were children, but they were adults for quite some time before the curse happened. And with their adult minds, even if they are stuck as children, they still know that these body parts should not be touched by others, or should be hidden.
Foe Yay: Hinted with Elysio mentionning he finds Jadina attractive, causing her to blush. It didn't went farer however.
subverted in Book 14 when Jadina kisses Abyss; not only Abyss has an extremely disgusted reaction, but it turns out she did so in order to transmit him a powerful anti-magic serum through saliva, weakening him.Raise your hand if you saw this coming.
It Was His Sled: Danael becoming Anathos' host. When the book came out, it was considered one of the biggest twists in the series. But thanks to the Nothing Is the Same Anymore situation after the Anathos Cycle, it has become really hard to miss.
Harsher in Hindsight: Danael's infuriated reaction against Halan when discovering he led his men to a Fate Worse than Death against the Darkhellions is presented as disproportionate and leads to a What the Hell, Hero? from Jadina, accusing him of letting his hatred of Halan get the better of him. But then we find out in Origins that his own childhood friend Saryn ended up with such as fate after being stung by a Darkhellion, suddenly giving much more sense to his reaction.
Jerkass Woobie: Shun-Day and to an extent Shimy, though the latter tends to be less jerkass as the story goes on.
Shun-Day becomes more Woobie than ever in Book 15-16, where we find out Gryf never really loved her and just used her feelings for him to speed up the creation of his Katseye and break up with Shimy. To make things worst, her father ends up killed (by her own mother with that), and she herself dies in a horrible way by the end of the Book.
Les Yay: The author never actually does this, but he loves playing it for laught:
At the beginning of Book 13, Shimy actually kissed Tenebris... only because she's drunk and trying to get her ex-boyfriend jealous. Later, having come back to her sense, Shimy is shown to feel disgusted and humiliated by what she did, while Tenebris teases her about it and asked her to warn her the next time she attempts that sort of thing...
Sobral himself pretended there was one between Shimy and Akitten, even publishing a trailer showing them talking about it. It turned out to be an April's Fool.
In Origines, Jadina forces Saryn to come in her tent and orders her to strip down. Next page, it's revealed she just wanted to use her as a replacement for her mirror to see if her new robes were fitting.
Played straight and horrifically subverted at the same time; Shimy did escaped her fate to become Anathos' reincarnation... only for Danael to have the place instead. More subverted when the heroes fail to save him and Jadina has to kill him. Sure, he came back, but no longer as a member of the Legendaries, and Word of God has confirmed he wouldn't be part of the group again.
In the ending of volume 18, all the Legendaries being killed and retconned out of reality, with only Danael, Shimy and Amy confirmed as having become completely different people. Absolutely nobody was surprised when the following arc, World Without, started focusing on them progressively recover their memories and former identities.
Most main villains cross it at least once, but Anathos is especially notable in that he did so many horrible things it's hard to pick exactly when he crossed it. Destroying a whole recently born planet for the sake of testing his newly gained power ? Manipulating an innocent elven girl into becoming his future host for his reincarnation ? Crippling all the heroes for the rest of their life ? committing mass murder and attempting to destroy Alysia again as a revenge for the Gods trapping for years after he destroyed the original Alysia ? Killing his own Dark Mistress ? Pick your choice.
Despite her sympathetic backstory, Kalandre crosses it by manipulating her followers and tried to sacrifice them all so she could kill the gods who wronged her if being directly responsible for the destruction of the Jenova stone or planning Anathos' release do not count.
Narm: Dark-Gryf's very first line isn't really easy to take seriously...
Gryf's Love Triangle with Shimy and Shun-Day post-Anathos Cycle is apparently intended to be perceived as a tragedy, but since the author keeps playing it comically and insert gags everywhere, it's rather hard to take it seriously.
The Scrappy: El Diablo; the character is a ridiculous and obnoxious villain with an ego so big he was actually willing to risk a possible cure to Alysia's condition (including his) just to keep his reputation as a great thief. Despite being a rather pathetic villain, he made the Legendaries look ridiculous when stealing them the cure, and they never had an occasion for a payback. Fortunately, he only showed up once.
Shoot the Shaggy Dog: Book 15-16 have a subplot involving Amy's desire of revenge on the Galinas, causing a conflict around weither Shun-Day, who is half-Galina as well as Skroa's daughter, deserves to die or not. It's revealed in Book 16 Amy actually is her mother, causing her to give up revenge and become Shun-Day's Mama Bear... only for Shun-Day to still die by the end of the Book at the hand of Sheiba's Clipped-Wing Angel form.
Similarly, the subplots about Razorcat having feelings for Nadkoko and Sheiba and Kel-Matu being a Childhood Friends end up unconcluded after both Razorcat and Sheiba are killed in their Clipped-Wing Angel form.
Squick: While they were at first played for laughs during the Anathos Arc, the occasional Panty Shots have later become a little too gratuitous to some fans' tastes, as the characters depicted still look like children.
Take That, Scrappy!: El Diablo is brought back in the "World Without" alternate timeline just to suffer a rather humiliating Curb-Stomp Battle after he tried to double-cross princess Shun-Day.
Saryn's fate at the end of Origins: her father is killed by Raptor, and, while she gets to avenge him, she ends up being stung by a Darkhellion and turns intoa Chaos Shade who attempts to murder Danael, causing Jadina to kill her. And she didn't even get to confess her feelings to Danael...
Jadina being forced to slay Danael at the end of the Anathos Cycle.
Razorcat's origin story, and his reaction when his mother order him to kill Nadkoko.
Suprisingly mostly averted; the changes from the Anathos Cycle were actually well-received by most fans.
Though some fans did complain about the books seemingly no longer going anywhere after the Anathos Cycle and the quest for the cure to the Jovenia incident being apparently dropped, as well as less action. The author actually listened to this complains, and posted an answer on his site to justify himself.
Too Cool to Live: Elysio, Shun-Day and Vangelis in the main series; Saryn and Alghar in Origins. Subverted twice in Book 3 of Origins with Samael.
Unintentionally Unsympathetic: Gryf doesn't emerge greater from the whole Love Triangle-affair with Shun-Day and Shimy. His fear that he may die because of the wound inflicted by Anathos and his decision to leave Shimy in order to Break Her Heart to Save Her don't compensate the fact that he lied to Shun-Day and only pretended to love her. He just used her feelings for him to speed up the creation of his Katseye and to break up with Shimy, and he doesn't seem that much tormented by it, his feelings about the whole ordeal being "Yeah, that sucks for her, but I needed to do that.". Doesn't help that, after Shun-Day is killed, it's her rival Shimy (of all people) who seems the most distraught by it, not him.
The Woobie: Elysio and Razzia, because of their respective backstory;
Saryn suits the place as well;
Woobie Species: The Jaguarians; despite having tried to live peacefully, they have been constantly chased and slaughtered like beasts by humans, when they are not captured and used in bloody gladiator-like games; They suffer from birth a sickness that turns them into blood-thirsty Berserkers whenever they are in proximity of other Jaguarians, unless they wear a specific jewel they can never remove and they have to stick on their forehead when reaching adulthood. In the end, they were forced to live hidden and secluded from the world.
The Animated Series:
Moral Event Horizon: Skroa crosses it in his first episode with his plot to feed the Boofankor Queen with an entire vilage.