The Tagreans are technologically advanced, capable of launching missiles into their planet's orbital space. They also have monorails (possibly based on magnetic levitation principles) and flying weapons platforms. The latter may be based on the dirigible principle, or may be heavier-than-air. In that case they would however need to employ some kind of anti-gravity technology, as they are not aerodynamic and can hover but have no visible rotors. Such technology seems beyond the Tagreans' demonstrated level, but not outside the realm of possibility.