Stargate: 10 Best Aliens In One Episode Only
1. Reese
Reese is an upbeat and fun young woman, one who only wants to have fun with her friends.
Her friends, as it turns out, are the Replicators. Reese, created by an unknown scientist, is the originator of all of the Milky Way Replicators and, indirectly, she is responsible for genocides rivaling the entirety of the System Lords.
She was created, in a similar fashion, by using nanites - a technology that is very similar to the Asurans in the Pegasus Galaxy. This later suggests that she may have originated from one of the Lantean scientists who escaped the Wraith. However, regardless of her origin, her childlike mind is dangerously unstable.
Daniel Jackson believes that, through her, they might be able to triumph over the Replicators while also gaining a valuable ally. O'Neill however suspects a greater malevolence in her, pointing out that she created Replicators that already had the power to replicate and grow - something that could only spell darkness for Earth.
O'Neill is forced to kill her by the end of the episode, thus causing the Replicators in the SGC to shut down. Daniel, for his part, believes that she shut them down herself.