Rick Riordan

Jason, Piper, and Leo, three students from a school for "bad kids," find themselves at Camp Half-Blood, where they learn that they are demigods and begin a quest to free Hera, who has been imprisoned by Mother Earth herself.

The fourth book in the bestselling Heroes of Olympus series by Rick Riordan, now with fresh and exciting new cover art by graphic novelist Nilah Magruder.
At the conclusion of The Mark of Athena, Annabeth and Percy tumble into a pit leading straight to the Underworld. The other five demigods have to put aside their grief and follow Percy's instructions to find the mortal side of the Doors of Death. If they can fight their way through

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Carter Kane and his sister must prevent the chaos snake Apophis from breaking free in a few days' time or the world will come to an end. To have any chance of battling these Forces of Chaos, the Kanes must revive the sun god Ra.

Ana Dakkar is a freshman at Harding-Pencroft Academy, a five-year high school that graduates the best marine scientists, naval warriors, navigators, and underwater explorers in the world. Ana's parents died while on a scientific expedition two years ago, and the only family's she's got left is her older brother, Dev, also a student at HP. Ana's freshman year culminates with the class's weekend trial at sea, the details of which have been kept secret....

When the goddess Artemis disappears while hunting a rare, ancient monster, a group of her followers joins Percy and his friends in an attempt to find and rescue her before the winter solstice, when her influence is needed to sway the Olympian Council regarding the war with the Titans.

"After angering his father Zeus, the god Apollo is cast down from Olympus. He must learn to survive in the modern world until he can somehow find a way to regain Zeus's favor"-- Provided by publisher.

Despite their best efforts, Carter and Sade Kane can't seem to keep Apophis, the chaos snake, down. Their only hope: find an ancient spell that might turn the serpent's own shadow into a weapon.

Will the Greek god Apollo, cast down to Earth in the pathetic mortal form of a teenager named Lester Papadopoulos, finally regain his place on Mount Olympus? Lester's demigod friends at Camp Jupiter just helped him survive attacks from bloodthirsty ghouls, an evil Roman king and his army of the undead, and the lethal emperors Caligula and Commodus. Now the former god and his demigod master Meg must follow a prophecy uncovered by Ella the harpy. Lester's...

Magnus Chase has always been a troubled kid. Since his mother's mysterious death, he's lived alone on the streets of Boston, surviving by his wits, keeping one step ahead of the police and the truant officers. One day, he is tracked down by a man he's never met -- a man his mother claimed was dangerous. The man tells him an impossible secret: Magnus is the son of a Norse god. The Viking myths are true. The gods of Asgard are preparing for war. Trolls,...

The Greek god Apollo, cast down to earth as the ungifted human teenager Lester Papadopoulos, and his demigod friends must go through the Labyrinth to find the third emperor--and an Oracle who speaks in word puzzles--somewhere in the American Southwest. The Greek god Apollo is still in the persona of ungifted human teenager Lester Papadopoulos. Now Lester and his demigod friends must go through the Labyrinth to find the third emperor-- and an Oracle...