The hardware was expensive and the software more so. Protecting the investment was a wide array of intrusion countermeasures, ranging from simple data barriers to the brain-frying IC known in the trade as black ice. In addition Magick Matrix was well supplied with roving deckhounds, the human computer-security specialists who jacked in to prowl the Matrix, alert for unauthorized users. Mortal flesh and tissue-bound minds lacked the purity and beauty of the elegant IC. Bound by organic nature, mankind also lacked the selfless devotion. But even the masters of such magnificent technology did not have absolute faith in it, and so they assured a weakness in their defenses.