Replicator

"We have an enemy in our home galaxy that is far worse than the Goa'uld."

- Thor

Replicators are advanced robots capable of reproducing themselves indefinitely, consuming all available resources in an area to create more of themselves.

Creation
"Don't be afraid. It's just a toy."

- Reese

The Replicators were created at an unspecified time in the past on a Human world where an android called Reese was created. This machine had a child-like personality and was feared by the natives of the planet. In order to keep herself amused, she created the Replicators which were to be her toys. As the population of the world grew more fearful of Reese and the replicators, she began to teach the machines to protect her and themselves. In order to accomplish this, they began the process of self replication. The Replicators grew too large in number, and Reese herself began to lose the ability to control them. After Reese lost control of the Replicators, they destroyed her world and everyone living on it. The Replicators abandoned Reese in pursuit of raw materials, and Reese, feeling guilty and abandoned, went to sleep. She was later discovered by SG-1 and brought to Earth where she was shot while trying to leave Earth with her newly created Replicators.

Asgard-Replicator War
"Overconfidence in our technologies has been our undoing. The entities learned from the very means that were employed to stop them. They have become a plague on our galaxy that is annihilating everything in its path."

- Thor

At some point, the Asgard race explored a world in their own galaxy and uncovered deactivated Replicator blocks. The creators were not present and were believed to have been destroyed by the Replicators. During the study of the machines, the Replicator blocks activated and began to assimilate Asgard technology, which allowed them to spread throughout the Asgard's galaxy. The Replicators became a plague that destroyed everything in its path. This resulted in the Asgard-Replicator war, which kept the Asgard's attention contained in their own galaxy as they attempted to defeat this robotic menace.

Eventually, the Replicators began taking over Asgard vessels and their tactics proved to be ineffective as the Replicators were fast learning machines. This meant that all attempts by the Asgard at defeating them meant that the Replicators simply grew more advanced by learning from the machines that were used against them. As a result, the Replicators began to close on the Asgard planet Othala. In desperation, the Asgard enlisted the aid of the people of Earth to help them combat this threat. With the aid of Samantha Carter, which in turn resulted in the destruction of the O'Neill-class ship prototype, they were able to stave off this initial invasion of their world. However, this was only a minor victory as the Replicators continued to be a formidable and dangerous foe.

Upon the rediscovery of Reese by SG-1, the Asgard took the android in order to find a weakness in the Replicators. Unfortunately, they were incapable of finding such a critical piece of information. Instead, they hatched upon a plan at containing the Replicator menace. Triggering an activation signal, the entire mechanical horde raced towards the Asgard planet Hala where a Time dilation field was activated which threatened to trap the Replicators indefinitely. However, the Replicators at this point managed to recover Reese and studied her form realizing that there were elements in her makeup that were superior to their own. This in turn led the Replicators to create Human-form Replicators which were composed of microscopic Nanite blocks. The First of these new intelligent Replicators was capable of piercing the Asgard time dilation device through a microscopic crack and reprogrammed it to serve their needs with the intention of increasing their numbers to such an extent that they would overwhelm the known worlds. However, SG-1 managed to convince Fifth to betray his kin and he activated the Asgard time dilation device though he was betrayed in the process leaving the Replicators trapped frozen in time.

Human-form Replicators and Fifth
"To increase our number. That has never changed. And now, thanks to the Asgard, we have all the time in the world. In a few short years, we will go forth as an army."

- First speaking of their goals

Despite the use of the time dilation device on the Replicators, it was projected by the Asgard that the machines even in this state would eventually be capable of deactivating the machine. As such, it was decided that Hala's sun would be collapsed into a black hole by increasing the gravity on its surface. It was believed that a combination of the time dilation field and the growing black hole would destroy the Replicators once and for all. Supreme Commander Thor was dispatched for this duty and he came into contact with Samantha Carter and Teal'c from SG-1 who came to ask for his aid. As they waited to see the end of the Replicators, Thor's vessel detected that a branch of the machines had split off from the main group and possessed the time dilation device which they used to counteract the effects of the black hole in a way that even the Asgard were incapable of explaining. As the Replicators were escaping, they came into conflict with Thor's vessel and Samantha Carter was abducted by the Replicators after they infiltrated the vessel through a Replicator block made missile that penetrated the Asgard shields.

Colonel Carter quickly came to realize that the Replicators were being led by a sole Human form Replicator, Fifth who had now taken charge of his kin. Due to the betrayal he faced at the hands of SG-1, he held a great deal of anger towards her and plotted to once again increase the Replicators numbers as was originally planned on Hala. To this end, he took his Replicator vessel to the new Asgard homeworld of Orilla where it was destroyed by an Asgard fleet but dozens of Replicator blocks survived and reached the surface of the planet where they began to infest the world thus threatening the stored minds of the Asgard that were waiting placement into new cloned bodies. Taking hold of the planet, the Replicators began a process of mining Neutronium in order to create new Human-form Replicators and it seemed that the destruction of the Asgard race was imminent.

However, Supreme Commander Thor went to Earth and saved the life of Colonel Jack O'Neill who had the knowledge of the Ancients in his mind. Using this information, they managed to construct a weapon capable of destroying the Replicators and something that they were incapable of defending against. Fifth himself came to realize that Samantha Carter would never love him and abandoned her on Orilla as well as an unknown number of his kin in order to escape the effects of the Replicator disruptor cannon and fled into hyperspace.

Though defeated, the Replicators were not destroyed and Fifth began to use his stores of Neutronium to create a Replicator copy of Samantha Carter.

Replicator Carter and Destruction
"You were right about one thing, Colonel. I was never working with Fifth, although he didn't know it."

- Replicator Carter

After escaping from their near destruction, the Human form known as Fifth began to create a duplicate of Samantha Carter known as Replicator Carter. This model then apparently escaped to the Milky Way in order to evade Fifth and enlisted the aid of the real Colonel Carter stating that she only wanted to live in peace. She claimed that the Replicators had developed a cipher that made them resistant to the Replicator disruptor weaponry. Working together with Replicator Carter, they deciphered what was believed to be a solution as the Replicators were coming to the Milky Way galaxy. When Fifth's vessel arrived in orbit, the weapon was activated by Replicator Carter who destroyed Fifth. After which, she revealed that it had all been a trick as Replicator Carter used Colonel Carter to help the Replicators develop an immunity to the disruptor technology. She then escaped through the Stargate and took command of the Replicator armies.

Some time later, the Replicators began their invasion of the Milky Way which began with Replicator Carter's infiltration of the Goa'uld Empire's summit station. The hordes of Replicators began attacking Goa'uld assets throughout the galaxy and began taking over their Ha'tak vessels. One such vessel encountered SG-1 and kidnapped Daniel Jackson who was placed in a facsimile world by Replicator Carter who disguised herself as Oma Desala in order to gain the knowledge of the Ancients from Dr Jackson. By the time Dr Jackson learnt of the deception, it was too late as Replicator Carter discovered about a weapon on the planet Dakara that was the only threat to her.

Taking her massive confiscated Ha'tak fleet, she assaulted Dakara which contained elements of SG-1, the Jaffa Rebellion and a fleet from the Goa'uld System Lord Ba'al. At the same time, despite protesting that she had no intention of invading Earth to Dr Jackson, the Replicator forces overrode Stargate Command's Stargate and began spilling from it to attack the Cheyenne Mountain complex. In addition, she sent one of her spider ships to Dakara's surface itself which began to assault the Free Jaffa and Tau'ri position there. It was only the intervention and sacrifice of Daniel Jackson that helped stall the Replicator forces who were frozen in place temporarily until Replicator Carter regained control of the subspace link. However, by this time, the weapon at Dakara was calibrated which fired a Replicator disruptor wave through a modified Stargate which dialled every planet in the galaxy. The wave disintegrated the Replicators and killed Replicator Carter, though the menace was not over.

Rebirth on the Odyssey
"Exactly why it'll be so effective in neutralizing the Ori fleet."

- James Marrick

Several years later in the Ori home galaxy while SG-1 was searching for the Ark of Truth, James Marrick under orders of the IOA used the Asgard computer core of the Odyssey to create a replicator. The replicator was specially modified by an unknown person who gave the program to Marrick; they were immune to the ARG, have all of the knowledge of the Odyssey and its systems, and a "self-destruct" built in to them. He tells them this is the IOA's contingency plan, to have the replicators eventually take over the Ori ships, since they didn't blow up the Supergate. When Carter releases the newly created replicator from the force shield, Mitchell shoots it with the ARG but it does nothing. The replicator quickly runs away and hides. In hiding it becomes a queen and begins to replicate. A grouping of these new replicators eventually break in to Marrick's cell and in attempt to stop the self-destruct from happening take over his body by sticking their legs into his back and controlling him. Meanwhile Mitchell locates the queen and sets up a small explosive device and waits for Carter's order to blow the queen to distract the rest of the replicators before they break into the Asgard core room.

While Mitchell is waiting the replicator-controlled Marrick arrives and starts to fight him. With the replicators controlling his body he seems to have much more strength and resistance to attacks. Mitchell and Marrick fought for some time until at one point when Mitchell pulled one of the replicator's legs out of Marrik's back. While this was happening Marrick was released from their control and spoke to Michell telling him of how the replicators took him to get to the "self-destruct" code which he managed to reveal was on the other side of the crystal used to create them. Right after this the replicators take back over his body and he begins beating up Mitchell some more until eventually Mitchell electrocutes him using a wire on the wall and stumbles out into the hallway while Marrick is stunned. During this time several soldiers are fighting off a large number of replicators who are trying to break through to the Asgard computer core. While this is happening the Odyssey is also getting attacked by four Ori warships. Mitchell finally blew the explosive after he sees Marrick walking out of the room towards him. However, this did not stop the replicators as from the body's ashes replicator blocks arose in the form of a human skeleton and moved towards Mitchell. While at the same time the replicator's began to break through the ceiling of the Asgard core room. Shortly before Carter retrieves the self-destruct program from the opposite side of the control crystal that Marrick used to create it and activates it. Right as the skeleton replicator reached Mitchell, it along with all of the rest of the replicators disassembled, finally ending the replicator threat.

Replicator Blocks
"Each individual building block is capable of exerting a reactive modulating monopolar energy field on other blocks allowing the replicators to assemble themselves into many forms. To our knowledge, the interior of each block contains the following; 2 million isolated keron pathways…"

- Thor

Each replicator is composed of a series of Replicator blocks. Each block is made up of many Keron pathways. It takes several blocks working together to make new blocks. Replicators are capable of forming many patterns determined by what they need to accomplish. Although Replicators usually take the form of "bugs," they can take other forms. The blocks are capable of absorbing large amounts of energy, which can empower them. The Asgard's dependence on energy weapons made it difficult for them to develop a weapon which could effectively counter the Replicator blocks. Tau'ri guns were capable of permanently damaging Replicator blocks (at most it would take two or three shots) but Human form Replicators are impervious to them.

The blocks were either capable of being assembled into the different types of Replicators or were formed into other shapes. They were able to create walls of blocks that served as barricades that prevented the enemy from escaping. Or they were capable of becoming tables and in one case were able to cover an entire planet's surface with blocks which conserved energy.

Behavior
"Their capacity for learning is extremely high. Each entity is capable of individual behavior, yet they all act with a common purpose."

- Thor

Replicators seek out the most advanced technology they can find, and incorporate it into their own being. As a corollary to this, Replicators are often capable of modifying a vessel to perform better than another of its class, to better defend themselves from threats. Both Asgard Bilskirnir-class vessel and Goa'uld Ha'taks were upgraded to well beyond the capabilities of their respective races under Replicator control. Generally, replicators will not attack unless threatened. This behavior will change, however, if there is a Human Form Replicator controlling them.

Each Replicator was capable of independent behavior but they all were unified in a single purpose which was self replication. They were remarkably adaptive allowing them to develop means at combating strategies that proved effective against them in the past and learn from them.

Termination
"It seems to have permanently disrupted all communication between the individual cells, rendering each one inert."

- Thor

The only weapon that was capable of destroying all forms of Replicators was the Replicator disruptor produced from the knowledge of the Ancients. This weapon attacked the links that held a Replicator together causing them to fall apart harmlessly.

It was only through the study of the cipher used in the weapon were the Replicators capable of gaining an immunity over it. This allowed them to adapt to varying frequencies of the disruptor after extended use.

Before the Replicator disruptor only Firearms where able to destroy replicators. They proved ineffective against Human Form Replicators.

"Spider" form
"Spider" Replicators are the basic variation of the replicator. They are the most seen and most numerous of all the replicators. The spider replicators are mainly tasked with moving out and collecting raw materials to bring back to the queen for replication. They try and find the strongest material they can to increase the strength of any newly created replicators. They are also equipped with a defensive spray that was capable of melting through metals in their path.

"Beetle" form
"Beetle" Replicators were seen on one occasion when the replicators were attempting to bring a Ha'tak to Sokar's former homeworld and Apophis' new base. After the ship had reached the planet SG-1 blew out the crystals of the engine, in retaliation the giant beetle controlling the engine split apart into multiple spider and beetles. The beetles were larger than the spiders and thus had the ability to jump farther.

Several Replicators of this type were sighted on the new Asgard homeworld of Orilla.

"Fly" form
Fly Replicators were encountered only once - in the episode. Though they are around the same size as the spider Replicators, they have shorter limbs, and wing-like structures on their back, making them greatly resemble a fly - hence the name. Despite this, fly Replicators could not fly or jump; instead, they could crawl on walls and fall from short heights such as a table. It is unknown if they could form a queen. Fly Replicators are likely an older model of Replicator, before they 'evolved' into their current state. These were less aggressive than other forms of Replicator, but later became aggressive as they responded to the needs of their maker Reese. The original one, made for Daniel Jackson to "play" with, was set up in a glass box and remained passive until Reese became emotionaly unstable. It then broke out of it's glass prison, but was soon destroyed by Teal'c. Reese was locked in a room, where she shut down a surveillance camera and used its parts to make a fly Replicator. That Replicator soon replicated to hundreds of others. This new horde of Replicators were shut down when Daniel convinced Reese to turn them off before she lost control of them - as indeed it was indicated they were beginning to do.

"Giant Beetle" form
"That is a big bug."

- Jack O'Neill

A "Giant Beetle" Replicator was seen on the Ha'tak that the replicators took control of and attempted to head to Apophis' home base. The "Giant Beetle" was at least 100-200 times larger then the a normal spider replicator. The replicators formed together into this form as they had reached critical mass and needed more technology to replicate. To do this many individual replicators formed together into the giant beetle around the engine of the ship. Using their power they managed to speed up the Ha'tak's hyperspeed by over 800 times it's normal max. When they arrived at the planet SG-1 quickly destroyed the control crystals of ship. When they did this the giant beetle split apart into a multitude of spiders and normal beetles.

Queen
The Replicator Queen was a unique variant of the Replicator form which was tasked with assembling more Replicators. This task was achieved by having the smaller drones deliver raw material to the queen, which used it to create more drones. The process required large amounts of energy, so a Queen would usually take position near some kind of power source. Every Queen encountered was immobile, requiring the other drones to guard and supply it.

The first Queen sighted by the SGC was present on a submarine on Earth around the location of where an Asgard vessel crashed. This form was embedded deep within the submarine and was producing more spider-type Replicators. It was destroyed by explosives from SG-1 which attracted the hostility from the remaining Replicators. A second much larger Queen was assembled upon the Replicators resurrection on the Odyssey. This version had tapped directly into the power conduits of the vessel in order to provide the energy to produce more of its numbers.

Human-form
Human form Replicators are Replicators that look like humans. They are composed of millions of tiny nanite cells. They were first created on Hala, after the Replicators discovered Reese. Not much is known about their construction, except that neutronium is a key element, which was why they invaded Orilla, the Asgard homeworld, as it was rich with neutronium.

Human form Replicators are capable of controlling other replicators, and can only be killed with the Replicator disruptor that Jack O'Neill constructed with the full knowledge of Ancient technology downloaded into his head.

Marrick


James Marrick was a Tau'ri whose body was taken over by the replicators in the Ori home galaxy.

A new ability was demonstrated by the Replicators which was the capacity on latching onto the spine of a Human or organic being and inserting a leg into the neck. From that point on, the creature became a puppet used by the spider form Replicator attached to it. It was capable of controlling the body against the will of its host and gave it increased strength as well as an immunity to pain. It was possible for the host to regain temporary control but only if the leg inserted into the neck is removed, however, it was only a matter of time before the Replicator re-asserted its dominance on the body.

After the body was destroyed in an explosion with all its organic components burnt away, the Spider form reconfigured itself taking over the entire host and using its Replicator blocks to assemble a skeletal based form.

Known Replicators

 * Reese (Creator)
 * First
 * Second
 * Third
 * Fourth
 * Fifth
 * Sixth
 * Eighth
 * Samantha Carter (Human Form Replicator)

Replicator Fleet
The Replicator fleet was a fleet of ships, most commandeered from their enemies, used by the Replicators during their war with the Asgard as well as their invasion of the Milky Way galaxy.

Known ships

 * Spider ship
 * Replicator cruiser
 * Replicator patrol ship
 * Several commandeered Asgard ships
 * Several commandeered and upgraded Ha'taks

Behind the scenes
In Stargate: The Ark of Truth, when Samantha Carter is looking at the code for either the Replicators or the shut down function, the code shown on the monitor is actually written in JavaScript. Apparently, it was taken from a real website.

The replicator blocks were both practical (real) props and computer generated images.

Trivia

 * Despite the fact that Replicators can repair themselves by re-assembling ther nanites, they were only seen repairing themselves on one occasion. This was their first appearance in Nemesis.