The "Terror Fist", arrived at the outer rims of the asteroid belt. They've switched "On" their cloaking device, after jumping out from "Hyper Space".
Their ship's hull, were laced with tiny LCD's. Enabling them to conceal their presence, by coating their entire ship with the holographic projections of their reflected surroundings. Making them, to appear invisible to the naked eye.
They've also, activated their "Heat Sinkers", "Thermal Dampeners", and "Thruster-Trail Suppressors". In order to mask their heat signatures.
While slowly cruising, using the "Pressure Wave Rotors" of their NTP drives (Nuclear Thermal Propulsion).
Reconnoitering, gathering intel, while formulating a strategy for their intended-assault on Central Command, before the arrival of the armada.
They've found a temporary hiding spot, within the dense clusters of the asteroid belt. As they lay in waiting, for the perfect window of opportunity, to commence the attack.