"Then, new methods of defense suddenly became possible..."

The Helios Drone is a compact laser platform that was designed for use in high-security facilities. Heavy, but the size of a human, the drone carries a laser weapon (which is central to the design), as well as rocket-based weaponry for armored insurgents. These drones were specifically designed to fight in groups, as about 4 can completely secure a compound.

Controls:
Pitch - move forward/backward
Roll - Move sideways
Yaw - Rotate
Throttle - Hover

Tips:
Gyros on small aircraft like this are unstable. Try to go easy on the yaw, and note that some random yaw movements will occur.
Use the roll sparingly.... it will cause the craft to lose stability.
The necessary throttle for hovering is hard to identify, but it is probably in the range of 30-35%.
Landing is extremely difficult, and you will most likely topple when you hit the ground. No worries though, as you can use the pitch thrusters to balance the drone.