[2][1] Hammerfall takes place on an unspecified planet,[a] where the Ila, believed to be a god and immortal, rules the Lakht, a huge desert, and all its villages from the holy city of Oburan.

Some of the villagers, including Marak, an abjorian fighter of the Kais Tain tribe, are afflicted with a "madness" that manifests itself in the form of voices and visions, and are outcast from their communities.

She queries Marak on the nature of these visions and voices, and, intimidated by her holiness, he tells her they appear to come from the east where there is a silver tower he is drawn to.

Guided by Luz's voice, Marak manages to avoid the bombardment from space and reaches Oburan, only to finds it in ruins, and the Ila and other survivors camped nearby.

The weather has changed—it is cold and often snows, but after several generations, Marak, whose makers have made him immortal, begins routine inspections of the transformed Lakht, and Luz prepares to release new creatures she has engineered.

A review in Publishers Weekly praised Hammerfall, calling it a "satisfying novel" that is a "blend of gorgeous, slightly knotty prose, deeply conflicted heroes, desperate action and nicely observed cultural details".

[4] Writing in the SF Reader, Elizabeth Kelley Buzbee described the book as a "world-class space opera" that explores "the low tech/high tech clash of cultures".

[7] A New England Science Fiction Association reviewer, Elisabeth Carey said that Hammerfall reads like a fantasy because it is written from Marak's perspective, a non-technological nomad, who probably interprets the technology he witnesses as magic.