The Races
The Wraith:
The Wraith are an antagonistic alien species. The Wraith are a hive-based species that grew to their level of power through technological knowledge comparable but inferior to the Ancients coupled with sheer mass of numbers. Wraith "feed" by "sucking" the life-force from a human being and are ageless. Natives of the Pegasus Galaxy, the Wraith are sentient, intelligent creatures who are humanoid in form, but insect-like in many other aspects such as their hive-based lifestyle and genetics. This is due to having been evolved from the tick-like insects known as the Iratus Bug into their current form after exchanging DNA with humans while feeding on them. They possess formidable physical strength, agility and co-ordination, all of which is enhanced depending how recently they have fed(more agile when they have recently fed). Intellectually they vary depending on their caste positions within their hives, drone soldiers are unimaginative and beast-like, while Queens possess considerable intellect and very powerful wills.
The Replicators:
Replicators are a race of self-replicating machines. The Replicators are primarily the main enemies of the Asgard, but their expansionist nature makes them a significant threat to all other lifeforms in the universe. Standard Replicators are composed of modular blocks, which can be compared to individual computers, that come together to perform several tasks. They have very high interconnectivity, and are able to communicate via subspace to other Replicators who may be light-years away. Every block contains two million isolated kiron pathways, that control the molecular cohesion of all Replicators. The blocks themselves are composed of whatever materials were available at the time of construction (implying an inability to transmute elements). Most Replicators however are made of more advanced alloys absorbed from Asgard ships, with whom the Replicators have been waging war for some time. It takes multiple blocks to create more blocks, although a single Replicator appears to be capable of self-replication.
The Goa'Uld:
Goa'uld are a parasitic alien race. They look like snakes but they normally insinuate themselves into the brains of larger animals, which they can then control. They find humans particularly suitable as hosts. Most Goa'uld pose as gods to control slave armies and are considered evil, egocentric, and megalomaniacs by those who do not worship them. "Goa'uld" means "son of the gods" or "children of the gods" in the Goa'uld language. They were named this by the Jaffa who carry them in their larval state. The higher echelon of Goa'uld formed a loose association of System Lords. However, there exists a rebellious offshoot of the species, the Tok'ra, that rejects the God/Slave paradigm of the mainstream Goa'uld and prefers to merge only with voluntary hosts. A singular Goa'uld is sometimes referred to as a symbiote, more often when the host and parasite have a free, benign, synergistic relationship as with the Tok'ra.
The Ancients:
They are called "Ancients" in the Milky Way, but are also known as Lanteans or Ancestors in the Pegasus galaxy and as the Alterans in their home galaxy, and they sometimes call themselves Anqueetas in their language. They are the most advanced races to have existed, having evolved for millions of years prior to the present day and reaching their level of technology long before humanity evolved on Earth. They are best known as the builders of the Stargates, the giant ring-shaped portals commonly used by Earth-based humans to travel and explore the Milky Way and Pegasus galaxies. They belong to the same race as the Ori. Millions of years ago, the first evolution of humanity, the Alterans lived in a distant galaxy along the evolutionary path to ascension. At the time, those who were later to be known as the Ori and the Ancients were not distinguished from each other, and lived in one society. However, a philosophical division emerged. The Ori grew more and more fervent in their religious belief, while the Ancients adopted a more scientific/rational outlook. Ultimately, their viewpoints diverged so much that the two groups split apart and began to oppose each other, culminating in the Ori attempting to destroy the Ancients. Instead of going to war, the Ancients decided to leave their galaxy, and began searching for a new home. The Ancients built Astria Porta (Stargates) across many planets, most of which were probably colonized by the race. Among the planets they settled was Earth, which they called Terra. The status of Earth in the Ancients' empire is disputed. However, as the planet's original Stargate, eventually discovered by SG-1 in Antarctica, was the oldest gate ever encountered, Earth was probably one of their more important worlds.
The Asgard:
The Asgard are a highly advanced and benevolent race from another galaxy, called Ida. The Asgard have visited Earth on many occasions, giving rise to the Norse legends. Despite the disapproval of the Asgard, the Goa'uld became a great threat to the Milky Way. The Goa'uld began taking humans as hosts during this time, which angered the Asgard as they realized humanity had a great potential, like its parent race the Alterans (Ancients). The Asgard and the Goa'uld went to war, but the Asgard were forced to pull out from the war to deal with greater threats in the Ida galaxy. Unwilling to completely give the galaxy over to the Goa'uld, the Asgard freed or transplanted humans on various worlds and became their protectors. The humans who couldn't comprehend their advanced technology as anything but divine magic thought they were gods (this is the origin of Norse mythology, and thus far only one protected planet besides Earth has realized its protectors' true power). To ensure the safety of these planets, the Asgard and the Goa'uld agreed in 'The Protected Planets Treaty' that the Asgard would allow the Goa'uld various benefits (the precise terms are unknown) and the Goa'uld would leave the humans alone. The Protected Planets Treaty could be expanded if both sides agreed to include other planets, which later protected Earth. This treaty was one of the few that all Goa'uld obeyed, as none wished to anger their more powerful enemies.
The Qaddisin:
(Kahd-DEE-sin)
The Qaddisin are a humanoid species, varying very little from tau'ri or ancients. They are a breed formed from the original inhabitants of their home planet, the Irin - human on the outside, and with relatively the same number of genes, differing only internally; Irin had additional skeletal plating, along the rib-cage and torso area, like a built in armor, and less brain-mass. Through experimentation and breeding into the Irin race, the Ancients created the Qaddisin. Now very humanoid, and lacking most of the extra-skeletal organs, with increased brain mass, they were designed for the singular purpose of being soldiers. Many have at least one advanced trait; vision, hearing, smell, strength, speed, or health beyond normal limits for tau'ri or ancients. The majority of Qaddisin race possess Ancient genes, strong ones at that. Being a race built by the ancients, the Qaddisin are familiar with Ancient technology, and use less advanced forms of it, often, their weapons are near the exact same ones introduced to them by the ancients. They are an independent race, reluctant to associate with other races. They fear the wraith, and try to keep their existance secret due to this. They believe the wraith will destroy them, just as they believe the wraith destroyed the ancients. Qaddisins are only ever born as twins or other multiples, amongst them, single births are unheard of.
(More to come)