Technologically, the Covenant are described in ' and ' to be imitative rather than innovative—most of the Covenant's sophisticated weaponry and propulsion systems are based on Forerunner artifacts, rather than the Covenant's own research. Covenant weapons are generally based on Forerunner technology and utilize plasma. These weapons are built around a battery that generates plasma and discharges it at a target. Frank O'Connor, Bungie's former public relations head, hinted that there may be something more to the Covenant's weaponry, saying "the actual technology is not plasma as we know it, but something far more dangerous, arcane, and destructive." A few of the Covenant's weapons are not plasma-based, including the Needler, which fires razor-sharp pink needles capable of "homing in" on organic foes and exploding. A weapons expert noted parallels between the Needler and ancient Greek Amazons painting their daggers pink as a psychological weapon in an issue of gaming magazine "Electronic Gaming Monthly".