The Hammer of Thor
"Thor's hammer is missing again. The thunder god has a disturbing habit of misplacing his weapon--the mightiest force in the Nine Worlds. This time the hammer isn't just lost, it has fallen into enemy hands.
The Sword of Summer
Magnus Chase has seen his share of trouble. Ever since that terrible night two years ago when his mother told him to run, he has lived alone on the streets of Boston, surviving by his wits, staying one step ahead of the police and truant officers.
For Magnus Chase: Hotel Valhalla Guide to the Norse Worlds
So you've made it to Valhalla. Now what? This "who's who" guide to the gods, goddesses, and other important figures of Norse mythology was commissioned by Helgi, who, after more than a millennium as manager of Hotel Valhalla, became fed up with answering the same questions from newly deceased heroes at check-in.