10 Deadliest Enemies Of The Stargate Universe
3. Replicators
The Replicators first appeared in the Ida Galaxy, which was the home of the Asgard. It's unknown how they ended up there, but they may have come from the Milky Way sometime long ago. Replicators were first created there when an advanced android made them as toys.
She told them to defend themselves and replicate at all costs, which resulted in their persistent need to destroy matter and replicate themselves from the base elements of what they destroyed. They targeted the Asgard in the Ida Galaxy due to their advanced technology, which they incorporated into themselves.
Eventually, the Replicators evolved from the large insectoid machines comprised of blocks to become beings that mirrored humanity. The human-form Replicators were far more dangerous than their blockier ancestors, as they were indestructible and relentless in their goal for advancement, survival, and continued replication.
By the time the Replicators were finally defeated, they had consumed nearly all available matter in the Ida Galaxy and had set their sights on the Milky Way. Had they been allowed to continue, they would have destroyed all matter they encountered on countless worlds, killing every organism they came across.
Fortunately, Samantha Carter and the Asgard developed a means of stopping them, but only after the Replicators had afflicted an unknown number of genocides across the cosmos.