A mixed-bag sequel to an excellent opening book. Sanderson's characters, as usual, are fun, the dialogue is snappy and (barring expletives) manages by and large to feel natural. The plot is compelling and well-paced, with some well-executed twists, and this certainly feels bigger than the first book, as it really expands the universe Sanderson is creating in the Cytonic series.

This expansion brings with it some of my reservations which reduce the rating to 3 stars. Having been confined to one setting largely in the first book, this sequel brings in a variety of new places and people for main character Spensa to adventure through/with/at. With this book, Sanderson has effectively established Cytonic as his Star Trek, for good and ill, introducing multiple alien species which are in most cases effectively humans but a different colour and with some different bits around the face. There's nothing wrong with this - It's fine sci fi tradition and it makes stories much easier to tell than if you have to deal with truly alien aliens (and to his credit Sanderson does include a few of these - His world-building here is at its best when

Spoiler

considering different approaches to gender, or introducing sentient smells

), but it brings with it some issues to be aware of, and which it is very clear Sanderson is not. Chief among these are that it is very difficult to do this and not to make the other alien species allegories for cultures and races on earth - Again, not inherently a problem and can be a great benefit for a writer like Ursula K Le Guin in The Word for World is Forest, but Sanderson gets caught in an awkward middle ground between treating them as racial allegories, having them actually be related to earth cultures, and keeping them separate for comedic or dramatic purposes, and the effect ends up being deeply uncomfortable and disappointing at points. Details in spoiler tags below.

Spoiler

This book has a moral of essentially accepting people and not judging them based on assumptions and prejudices. However, the book is too light-hearted really to deal with the fact that its protagonist is racist in ways which have unpleasant real-world resonances. Descriptions of the Diones through Spensa's eyes fixate on their unusual-to-her facial expressions and inability to smile without it being 'creepy'. This much can perhaps be explained as being the world through Spensa's prejudiced and entirely human-centric viewpoint, but then we move to facts of the world external to Spensa, such as the Kitsen, led by their 'furry little dictator' Hesho, who have had democracy forced upon them but are utterly incapable of understanding it or of going against their former leader. This is used for comedy throughout, and could work as a broad satire, but the many links made to existing East Asian cultures, particularly in Japan, and the fact that this is made text by a passage mentioning that the Kitsen had visited East Asia often in the 'pre-industrial era' causing significant cultural transfer, suddenly makes the satire much more pointed and much less pleasant. Let's also not even get into the use of outdated and offensive cultural evolutionary theory treated in this book (and largely across the genre) as essentially fact or the book's admittedly low-level engagement with Ancient Alien 'theory'. I genuinely don't think there was any intent or malice in Sanderson's use of these ideas and I do not think he is racist, but he has waded into a genre fraught with issues and failed to engage with any of them, has indeed enthusiastically embraced some of the nastier approaches to Star Trek-style space opera. Hoping for more nuance from Books 3 and 4.