The Invid were a slug and insect-like race responsible for the Third Robotech War. They had a symbiotic relationship with the Flower of Life -— the plant that was the source of protoculture. Historically, they were the enemy of both the Robotech Masters and, more distantly, the Haydonites. Their invasion of Earth after the Second Robotech War also pulled them into conflict with humankind.
Homeworld and empire
The Invid were from an unknown planet since destroyed by the Haydonites. More recently, they had made their home on Optera, which is relatively near the home world of the Robotech Masters.
After the loss of Zor's battle fortress, the Invid took advantage of the weakening empire of the Robotech Masters and built their own empire from the ashes of the old.
After the arrival of the Pioneer Expedition searching for the home world of the Zentraedi and the Robotech Masters, the Invid empire began to collapse. The alliance of the Sentinels with the Robotech Expeditionary Force led to the overall collapse of the Invid empire, including the loss of Optera.
The Invid are ruled by an all-mother calling herself the Regess, and an all-father called the Regent. The Regent led the Invid forces encountered by the Pioneer Mission, while the Regess led the invasion of Earth that led to the Third Robotech War. The Regis and Regent are considered mates, though their relationship is less than cordial. Both rulers have their own vision for the place of the Invid in the universe, and the methods that will lead them there. While the Regis is more concerned with the evolutionary preservation of the race, the Regent is more focused on their military advancement.
The Flower of Life
The alien plant known as the Flower of Life is inexorably tied to the survival of the Invid race. When the Robotech Masters discovered protoculture while studying this plant, they believed the Invid unaware of its properties. The Zentraedi, under orders from the Masters, were sent to harvest as much of the Flower as they could, then defoliate the entire planet of Optera.
The destruction of Optera's ecosystem changed the Invid.
Behind the scenes
In the original Robotech cartoon, the Invid are never shown outside of their Fighter Suits as adults, although the narrator claimed that the Invid are a protoplasmic race. They were portrayed as slug-like in concept art for Genesis Climber MOSPEADA, of which Robotech: The New Generation was derived from. Their original name was the Inbit.