Sonic the Hedgehog in Castle Robotnik
Publisher: Virgin Books; Ebury Publishing
Published: January 20, 1994
Format: Paperback
Number of pages: 182
ISBN-13: 9780426204053
Subjects: Science fiction
Description: It's the FrankenSonic monster! In this, the fourth book in the series, Doctor Robotnik plots to defeat that pesky hedgehog once and for all - by building a bolt-together version of Sonic.

Wherewolves, vampires and mummies lie in wait for Sonic and his sidekick Tails as they venture into Robotnik's mountaintop castle for a cataclysmic confrontation.