10 Deadliest Enemies Of The Stargate Universe
7. Aschen
One of the deadliest enemies to ever appear in the Stargate Universe were so seemingly benign and helpful, it wasn't even clear that they were enemies for a long time. The Aschen were introduced through two episodes that took advantage of the gate's time travel trick, and they were dastardly.
The Aschen were the most technologically advanced people in the galaxy, though they didn't have any gate addresses. Instead, they relied on interstellar travel, which limited their expanse, which was their primary purpose. The Aschen found a world that was technologically less advanced than themselves, so they could form an alliance.
At first, everything seemed to be perfect, as the Aschen cured all disease, increased the human lifespan significantly, and easily defeated the Goa'uld. Unfortunately, it was all a ploy, and the Aschen's purpose was entirely self-serving. The world's they allied themselves with were slowly converted into agrarian resources they could exploit.
They did this by introducing forced sterility into the population, which resulted in a decline and eventual dying-off of the majority of a planet's population. Once that process was complete, the Aschen would reinstall themselves as leaders over a weakened society and use them for their resource-needs.