Invid Factions
By the time of human involvement with Robotechnology, the Regent and Regis have largely ceased to interact and divided the race between them. The Regis leads the invasion of Earth while the Regent presses his assault against the remnants of the Masters' empire on their own homeworld of Tirol, left virtually defenseless in the wake of the First Robotech War (which saw the near-obliteration of the Zentraedi) and the departure of the Robotech Masters (to Earth, in search of the Protoculture Matrix). Ironically, this arrangement leaves humanity to confront both of the monarchs, the Regent battling the Robotech Expeditionary Force (REF) when it arrives in Tirol and the Regis arriving to take Earth from Southern Cross forces already depleted by a prolonged war with the Masters.
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