Rick Riordan

Thor's hammer is missing again. The thunder god has a disturbing habit of misplacing his weapon—the mightiest force in the Nine Worlds. But this time the hammer isn't just lost. It has fallen into enemy hands. If Magnus Chase and his friends can't retrieve the hammer quickly, the mortal worlds will be defenseless against an onslaught of giants. Ragnarok will begin. The Nine Worlds will burn. Unfortunately, the only person who can broker a deal

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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.

Percy Jackson, now a high school senior, needs three recommendation letters from the Greek gods in order to get into New Rome University. He earned his first one by retrieving Ganymede's chalice. Now the goddess Hecate has offered Percy another "opportunity"--all he has to do is pet sit her polecat, Gale, and mastiff, Hecuba, over Halloween week while she is away. Piece of cake, right? Percy, Annabeth, and Grover settle into Hecate's seemingly endless...

"The Greek and Roman demigods must simultaneously prevent the earth mother, Gaea, from waking and stop war from breaking out at Camp Half-Blood"--Provided by publisher.

After a summer spent trying to prevent a catastrophic war among the Greek gods, Percy Jackson is finding seventh grade unnervingly quiet. His biggest problem is dealing with his new friend, Tyson, a six-foot-three, mentally challenged homeless kid who follows Percy everywhere. But things don't stay quiet for long. Percy soon discovers that there is trouble at Camp Half-Blood: the magical borders that protect Half-Blood Hill have been poisoned, and...

"Greek and Roman demigods from the Prophecy of Seven must work together to seal the Doors of Death--and help Percy and Annabeth escape the Underworld in the process"--Provided by publisher.

In this story inspired by Jules Verne's "20,000 Leagues Under the Sea," Ana Dakkar, 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, makes astounding discoveries about her heritage and puts her leadership skills to the test against deadly enemies from a rival school.

At last, the breathtaking, action-packed finale of the #1 bestselling Trials of Apollo series is here! Will the Greek god Apollo, cast down to earth in the pathetic moral 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....

The formerly glorious god Apollo, cast down to earth in punishment by Zeus, is now an awkward mortal teenager named Lester Papadopoulos. In order to regain his place on Mount Olympus, Lester must restore five Oracles that have gone dark. But he has to achieve this impossible task without having any godly powers and while being duty-bound to a confounding young daughter of Demeter named Meg. Thanks a lot, Dad. With the help of some demigod friends,...

"Percy Jackson is about to be kicked out of boarding school...again. And that's the least of his troubles. Lately, mythological monsters and the gods of Mount Olympus seem to be walking straight out of the pages of Percy's Greek mythology textbook and into his life. And worse, he's angered a few of them. Zeus's master lightning bolt has been stolen, and Percy is the prime suspect." -- from front jacket flap.