Vortian

The Vortians  are a race of intelligent goat-like humanoids from the Invader Zim Universe. Native to the planet Vort, they are brilliant scientists, and designed weapons for their former allies, the Irken Empire, until the latter race cut the alliance short and enslaved the Vortians.

History
Vortians are responsible for most of the Irken's technology resources, for two reasons. The first reason was because, in the past, the Vortians were allies of the Irken Empire and supplied advanced military gear, and the second reason is because of its conquer by Invader Larb, and they are now forced to supply military gear. Not all Vortians are prisoners; some have escaped and can be seen briefly on planet Foodcourtia. Eric the Blob mentioned that he had installed similar security systems to the one in Shloogorgh's Flavor Monster in Vortian prisons, but they were discontinued after multiple Vortian prisoners escaped by "hiding deep in garbage cans". This could explain Lard Nar 's freedom and could pose as an excuse as to why there may be any free Vortians.

Vortians created devices such as The MegaDoomer and Minimoose. However, it is suspected the Vortians have shown small signs of rebellion by purposely flawing their creations. For example, the Vortian-designed MegaDoomer oddly cloaked itself, but not its user, and, for obvious reasons, Minimoose isn't any more reliable than GIR as an evil minion sidekick. Also worth noting is that Vortian Prisoner 777, an acquaintance of Zim, was willing to hand over the Massive's schematics, even though he knew, and warned, that it could infuriate the Irken Armada.

The only piece of technology shown during the series of purely Vortian design is the Resisty Ship.

Biology
The Vortians are humanoid in structure, and are around the same height and of the same proportions as the average Irken (about five feet). They have gray skin, and possess goat-like characteristics such as hooves, and a pair of large, flexible horns atop their heads, which are similar to Irken antennaes. Their mouths have zipper-like teeth and one worm-like tongue. They also have two small eyes in the typical place, but lack ears or a nose. There doesn't seem to be much of a difference between male and female Vortians.