Bizarro Episode: Episode 23, which deals with an evil pharaoh being resurrected from the dead with plans to destroy the world.
Esoteric Happy Ending: The Black Hammers lost all the fairies they captured and the Tree of Life is saved but Michel dies in order to rejuvenate the tree, and Kim leaves the island. It's played as more happy than bitter, as Michel will be reborn later, Biam is with the fairies again, Kim reflects on her experience fondly and feels that Michel will remember her when he does return... but in the meantime the bad guys still have the floating castle, and without Michel or Kim around to protect them, the fairies could easily get captured again and start it all over.
Moral Event Horizon: In a flashback in episode 6, Salome stole Dr. White's inventions and killed him during her escape. The same episode has her trying to outright get Kim killed by tricking her into walking off a cliff, and later she uses an illusion of Kim's father to trick her into destroying her plane.