The Sword of Summer established Magnus Chase as a worthy addition to the Riordan universe — a different sensibility from Percy Jackson, Norse mythology rendered with the same confident lightness as the Greek material, and a protagonist whose homelessness and grief gave the book unexpected emotional weight. The Hammer of Thor builds on all of that and adds Alex Fierro, who immediately becomes one of Riordan’s best characters.

Thor has lost his hammer. Again. (This is, apparently, a recurring problem.) Its location is in the hands of a giant who wants to marry a Valkyrie, and Magnus and his crew — Sam, Hearth, and Blitz — have to retrieve it before the marriage happens and Ragnarok is triggered. The plot is deliberately structured around the original myth while doing something meaningfully different with it.

Alex Fierro

Alex is gender-fluid, a child of Loki, extraordinarily competent, and immediately suspicious of Magnus in ways that are entirely reasonable given her history. Riordan introduces her with the same directness he brings to all of his representation: her gender fluidity is not a plot point to be resolved or a lesson to be learned, it is simply who she is, and the book treats it accordingly.

She is also very funny and very good in a fight and carries a garrotte that she uses with genuine expertise. She is, in short, excellent.

Sam

Samirah Al-Abbas continues to be one of the best characters Riordan has created — balancing her Islamic faith, her Valkyrie duties, her arranged engagement, and her complicated relationship with her father Loki with the kind of grace that comes from genuinely careful characterisation rather than a checklist of attributes. Her chapters are consistently among the book’s best.

The Mythology

Riordan’s Norse material continues to be excellently sourced — he clearly knows the Eddas, and The Hammer of Thor’s treatment of the Thrym myth is both faithful to the original’s spirit and genuinely funny in its own right.

Why YA Readers Will Love This

For readers who started with Percy Jackson and want more: this series rewards the investment. Magnus’s world overlaps with Annabeth’s (she appears in the first book and is referenced here), and the Norse cosmology adds genuine novelty to a universe that could have become repetitive.

For younger readers encountering gender-fluid characters in fiction for the first time: Riordan handles Alex’s identity with the same matter-of-fact normalcy he brings to every form of diversity in his books. Alex is not explained to the reader. She is introduced as a person.

For all readers: The Hammer of Thor is genuinely funny, well-plotted, and moves exactly as fast as it should. Riordan at his most reliable.

Published: October 2016 · Genre: Middle grade/YA fantasy · Series: Magnus Chase and the Gods of Asgard, Book 2

Frequently Asked Questions

What is The Hammer of Thor about? Thor has lost his hammer — again — and its location is in the hands of a giant who wants to marry a Valkyrie. Magnus and his crew must retrieve it before the marriage happens and Ragnarok is triggered. The plot is ‘deliberately structured around the original myth while doing something meaningfully different with it,’ and the book introduces Alex Fierro, described as ‘immediately one of Riordan’s best characters.’

Who is Alex Fierro and why is the character significant? Alex is gender-fluid, a child of Loki, ’extraordinarily competent, and immediately suspicious of Magnus in ways that are entirely reasonable given her history.’ Riordan introduces her ‘with the same directness he brings to all of his representation: her gender fluidity is not a plot point to be resolved or a lesson to be learned, it is simply who she is, and the book treats it accordingly.’ The review calls her ‘very funny and very good in a fight’ and simply: ’excellent.’

How is Samirah Al-Abbas characterised in The Hammer of Thor? Sam is described as ‘one of the best characters Riordan has created — balancing her Islamic faith, her Valkyrie duties, her arranged engagement, and her complicated relationship with her father Loki with the kind of grace that comes from genuinely careful characterisation rather than a checklist of attributes.’ Her chapters are ‘consistently among the book’s best.’

How accurate is Riordan’s use of Norse mythology in The Hammer of Thor? The review says Riordan ‘clearly knows the Eddas, and The Hammer of Thor’s treatment of the Thrym myth is both faithful to the original’s spirit and genuinely funny in its own right.’ This is positioned as one of the series’ consistent strengths — deep engagement with source material that produces adaptation rather than mere imitation.

How does the Magnus Chase series connect to Percy Jackson? Magnus’s world ‘overlaps with Annabeth’s — she appears in the first book and is referenced here — and the Norse cosmology adds genuine novelty to a universe that could have become repetitive.’ For readers who started with Percy Jackson, the review says this series ‘rewards the investment’ precisely because it brings genuine new mythology rather than simply extending the Greek material.

Further Reading from Authoritative Sources

  • The Hammer of Thor — Wikipedia’s The Hammer of Thor article provides publication details and series context that helps readers understand the novel’s place in the Magnus Chase trilogy and its relationship to the broader Riordan universe.
  • the Eddas — Wikipedia’s Prose Edda article contextualises the primary source material for Norse mythology that Riordan draws on, helping readers understand the Thrym myth’s original form and what Riordan is adapting.