After the decimation of his Legion on the killing fields of Isstvan V, the primarch Corax sanctioned an accelerated implantation process to create new Raven Guard - a process subverted in secret by his enemies. But inspite of thei horrendous mutations, the warriors of the Raptors still stand ready to do their primarch's bidding. When a watch-pack of Space Wolves legionaries arrives unannounced, it falls to Lieutenant Navar Hef to greet their warlike kinsmen and decide whethr or not they might be hidin flaws of their own...