BAD UNICORN

Harry Potter meets Diary of a Wimpy Kid in an initially witty debut that ultimately collapses.

Seventh-grader Max Spencer isn’t athletic, clever, brave or particularly kind, and he sure isn’t popular. But he is the long-lost heir of the arch-sorcerer who created the Codex of Infinite Knowability, which only Max can read. Inaccessible in our magic-free dimension, the Codex’s powerful spells are coveted by the mages of other realms; to retrieve it, they enlist the most vicious flesh-devouring monster known: Princess the Destroyer, the eponymous bad unicorn. The setup cleverly skewers common fantasy tropes, and delightfully gruesome vignettes of mayhem add extra spice. Though wildly uneven, the gags fly so rapidly that some are bound to provoke snickers. Unfortunately, Max has been rendered as such a convincing loser that it’s hard to root for him as a hero; his friends are shallow clichés and offensive stereotypes, and the remaining characters are merely walking punch lines. Identifying target readers isn’t easy; the protagonists’ ages (and the proclivity for crude humor) suggest a middle school audience, who will be baffled by plot twists relying upon the mechanics of ’80s-style arcade and tabletop games (let alone by the Al Gore jokes). The clunky, stilted prose is littered with $20 vocabulary. And when the many rambling discursions eventually converge to a genuinely gripping climax, too many storylines are simply dropped, apparently forgotten.

Like a comedian repeating the same joke louder each time: at first funny, then annoying; finally, just sad.