Samus Aran 8 (also known as SA-C8 or 8) is a character from Metroid Avenger 2: Revenger. A clone of Samus Aran, who committed suicide three years prior to Revenger, SA-C8 was the only successful clone of Samus Aran (the other seven were highly deformed). The G.F.S. Artemis was trying to extract the Metroid Hatchling's DNA that was implanted in Samus during Metroid Fusion (DNA came from her Power Suit).
The new Samus clone is a hybrid of Samus herself and the Metroids, giving her great strength, acidic blood, and empathy with the creatures. While Samus does retain a human side, she is also more violent than the original. She also retains all of the original Samus' memories, mainly concerning her relationship with the young Roy Dane and her previous missions.
The clones of Samus were created as experimentation with the Metroids. The quarantine officer, a character from Metroid: Other M, asked to keep her alive for study; the request was approved. The DNA of the Metroid hatchling inside of her, once extracted, also resurrected the Metroid hatchling, who accompanied Samus.
Later, when Roy Dane was arrested and brought onboard the G.F.S. Artemis, he encountered Samus, who was also in jail for attempting to kill the quarantine officer. Their friend Ron Green from Metroid: Avenger followed Roy onto the flagship along with friend Kim Irene, who absorbed Samus' spirit.
Knowing this, the Federation employees attempt to extract the Phazon in Roy's body (Phazon he had absorbed in the ending of Avenger, when trying to kill The Exterminator once and for all) and extract the spirit of Samus in Kim's physical being. The Phazon is extracted from Roy, but Kim manages to escape and finds Ron and Samus. Later, the group discovers that the Federation have found and captured more Metroids in the Darch Star Cluster, where Ron had explored in Avenger. The Metroids escape their containment unit by killing one of each other and using the acidic blood to make a hole in the floor. They absorb the Phazon, becoming Delta Metroids, and wreck havoc on the crew of the Artemis.
Roy, knowing this, attempts to kill the Metroid hatchling overnight, though Samus greatly defends it. Roy mistakenly sticks his knife into Samus' chest. Thinking he's killed Samus, she tells him about her enhancements, and he stops trying to kill the hatchling. Realizing that Metroids are about to break into the room, they leave by burning the lock on the door with Samus' blood.
Along with several other mercenaries onboard the Artemis, they set the ship to crash land on Earth. Exterminating Metroids along the way (though not all of them), they believe that crashing the ship will destroy all the Metroids aboard.
While escaping the Artemis Samus finds the lab containing the first seven clones of her. At the pleading of number 7, Samus destroys the lab with a Power Bomb. A Gamma Metroid takes Samus from under the floor and carries her to the Metroid stronghold, where she sees a super-deformed Zeta Metroid kill the Queen Metroid. Although Samus escapes, the Zeta Metroid follows her and boards the ship that she and her friends are escaping on.
Samus, Roy, Ron and Kim escape in Ron's ship as the ship nears Earth. The Zeta Metroid attacks Samus and Roy, but Samus kills it by using her own blood to burn a hole. She tricks the Metroid into thinking that she'll die with it, but Roy throws her a rope to get her back on the ship. The group radios the United States to fire a Missile to destroy the "asteroid" and prevent the Earth's destruction.
The survivors look at Earth from the open door, marveling at its beauty. The group then lands on Earth, beginning Metroid Avenger 3.