Bugs. That's what soldiers call them. Creators. That's what the Nazzadi called them. The Tibetans call them Migou - the abominable snowman. They are the greatest enemy humanity has ever faced.
The alien creatures of Yuggoth walked the Earth long before the first ancestors of man, They experimented on the early hominids. When the climate changed. most of them left. The few that remained behind stayed only to mine precious minerals needed at home. They continued experimenting on Humans, if only to master another species. The Migou were always the ones doing the abducting - the "Greys" were false memory Implants.
The Migou are said to come from Yuggoth - we call it Pluto. Their underground cities are hidden away from prying eyes. Here, the Migou live in giant crystalline and metallic cities. They have a rigid hierarchy, and intense focus, making them the most efficient war machine on the planet. The drastically different atmospheric and gravitic conditions on Earth seem to affect them little.
To call them an alien insect would not be entirely accurate.They are more a strange hybrid of insect, crustacean, and fungus-like traits. Dozens of cilia hang from their faces and giant membranous wings propel them through the air. On the ground, they skitter on a host of exo-skeletal legs. The Migou communicate through a complex mix of body language, the motion of their cilia, and the buzzing of their wings. It is impossible to understand - the New Earth Government has never even come close to cracking it. However, it turns out that they can mimic a buzzing voice box and they can talk to us.
The Migou don't feel in the same sense as mortals do. It's not that they are emotionless - it's more that their emotions are totally alien. That missing piece of the puzzle makes them hard to predict.
Since their home is a cold and desolate place, they took the areas that made them most comfortable first - Arctic tundra and mountain tops. Their main settlement on Earth is the Antarctic. But they've been getting restless lately and have started once again moving into the world. Alaska is failing to them and they now threaten the very heart of the New Earth Government - North America.