Darkspawn
CONCEPT
The evil horde of twisted beings that, under the leadership of an Archdemon, threaten all of Thedas once every few hundred years, in the form of a Blight. They are essentially generic fantasy orcs, goblins, and trolls, lumped together as one race and given different names.


The diseased creatures known as darkspawn mysteriously appeared in  the Deep Roads  over a thousand years ago, viciously attacking the             dwarves and  eventually pouring out onto the surface during the first            blight.  After the              Archdemon  was slain and the horde defeated, they retreated back into the Deep  Roads. There have been 3 subsequent blights since, each of them almost  completely annihilating                Thedas.     
 Origins 
   
 The true origin of the Darkspawn is currently unknown. The only  existing explanation comes from the        Chantry,  who claim that they were created when the magisters of the ancient  Tevinter Imperium used blood magic to sunder the veil and physically  enter the           Fade. These  magisters dared to enter the golden city, the holy seat of the Maker,  in an attempt to usurp His thrown and seize ultimate power for  themselves. They corrupted the city with their presence and were cast  down by the Maker, who cursed them and transformed them into the vile  and corrupted creatures known as the darkspawn. The Chantry refers to  this event as the first sin, the very reason that the maker turned his  back on humanity and his creation. 
  
 This story is never  presented as fact however. Indeed, many characters refer to it as a    Chantry lie, an attempt to justify the oppression of all those born with  the ability to wield           magic.
 Reproduction
  The various species of darkspawn have no females of their own. Instead,  they rely on the other races of Thedas for their survival. Darkspawn  kill most males on sight, but try to capture as many females as possible  alive. They drag these females underground to their lairs where they  force them to eat the corrupted flesh of their fallen brethren.  Resulting in great pain and horrific transformations. Few females  actually survive this process, but those that do, live to become the  gruesome  broodmothers.                                                                       
 Each race  produces different types of broodmothers and thus, offspring. 
  ·           Human females  produce hurlocks.
  ·            Dwarven females produce genlocks.
  ·           Elf females  produce shrieks.
  ·            Qunari females produce ogres.
  Each individual broodmother can give birth to thousands of darkspawn  over her lifetime.
 Hierarchy
  The darkspawn are linked through a hive mind. Intelligent darkspawn  such as alphas or emissaries can exert a limited amount of control over  small bands, but only the mighty Archdemon has the power to command the  entire horde.   Normally the darkspawn are very chaotic and disorganized  and choose to remain underground. Deadlocked in a constant war with  their sworn enemies, the dwarves, they only rarely venture to the  surface in small war bands. It is only when they find a slumbering Old  God and transform it into an Archdemon with their taint, that they unite  as a race and march to the surface in an effort to eradicate all life  in Thedas.
 Darkspawn appear to have no craftsmen or  workers, instead relying on equipment scavenged from fallen enemies or  artefacts left behind by the dwarves when they fled the Deep Roads.
 The taint
 The darkspawn carry with them  a disease called the taint. The taint is the source of their strength  and sustains them, eliminating the need for nutrition. Areas controlled  by the darkspawn become corrupted by this taint, which manifests in the  form of fleshy growths and tendrils, transforming and eventually killing  most life forms it comes into contact with. Creatures that are  corrupted by the taint will serve the darkspawn and also inherit some of  their traits (like fast regeneration and increased sensitivity to  light), although their usefulness is limited. Indeed, the taint will  kill most within months. 
 The taint also  allows the darkspawn to hear the song of the Old Gods. A magnificent  chorus that claws at their minds and compels them to obey, to seek out  the Old Gods and free them from their ancient underground prisons.
 Magic
 As with most sentient races, some  darkspawn are born with the ability to wield magic. These individuals  are called emissaries and can be either hurlocks or genlocks. Emissaries  are more intelligent than their brethren and can even utter words and  short phrases during combat. They often act as the leaders of small  groups and the taint grants them access to unique forms of dark magic  that other races have no knowledge of.
 Disciples
 The highly intelligent talking darkspawn known as      The Architect  has developed a ritual which involves the drinking of       Grey Warden  blood, which grants the darkspawn immunity against the song of the Old  Gods. With their minds freed, these disciples develop free will and gain  the ability to think and speak. These darkspawn are highly intelligent  and skilled with weaponry, with the ability to use complex war tactics,  such as     siege warfare.  However, due to their underground isolation, they are socially inept  and find it hard to anticipate and understand the reactions and  behaviour of humans. 

http://media.giantbomb.com/uploads/3/30014/1296407-architect_02_screen.jpg
The Architect with his eccentric and outlandish fashion sense
  
 Not all disciples remained loyal to The Architect however, with some  defecting to serve The Mother instead. These disciples were referred to  as “heretics”.