The Shifters, or Shedarian Shifters as they are sometimes called, are a group of beings founded by an offshoot of the original experimental population of Shedarians that escaped the Shyedarian Age of Fire. Early in the foundation of the settlement on Shedar IV, a small group of individuals felt an inexplicable calling to take a shuttle and explore a certain distant region of space. What they found there is a mystery, and the coordinates of that region are lost, but it is known to be the birthplace of the Shifter movement.
The Shifters get their name from an A'rthan technology that they uncovered. Related to the Shyedarian Change Virus, this technology lives in all Shifters, and gives them the ability to change their physical form over time, when presented with a genetic sample as a template. However, it is only one of many A'rthan technologies they have discovered.
The goal of the Shifters is to acquire enough A'rthan technology and A'rthan knowledge to take the place the A'rthans held in the galaxy as overseers. To achieve this goal, they use whatever tactics will yield them results. They have been known to orchestrate assassinations and politically destabilize entire regions of space just so they can slip in and search for A'rthan artifacts without being hindered. Any time the presence of A'rthan technology becomes public, you can be sure that Shifter operatives will be there to track it and eventually try to take it.
The Shifters take no interest in politics, and stay out of conflicts between systems. Their only interest is in A'rthan lore, and they will only try to alter events in the Zulu Sector when it will help them achieve their goals. Fortunately, their numbers are relatively small, so they are loathe to take on any systems or organizations head-on. However, their mastery of A'rthan technology is indisputable, and they make extremely dangerous adversaries.
Knowledge about the Shifters is generally scarce among most galactic civilizations. Most higher level government and military officials are briefed on what is known about them, but at levels below that, they are known only through rumors, and many beings do are not even convinced they exist.