A Blood Congress is a sentient collection of blood cells residing in the body of a human carrier. The blood cells manifest as free-floating blood cells which enter and exit their hosts through its orifices or mucus membranes.
The cells that make up a Blood Congress do not all have uniform views. They can go to war with each other, even causing their host bodies to explode in the process.
Blood Congresses can take over the mind of their hosts by neuroprogramming their brains.
A Blood Congress hired by an unknown client to destroy the Authority takes advantage of Grunge’s visits to Swift on the Carrier. It lures Grunge and sets up a cognitive tripwire in his brain makes use of his power to rearrange the molecular structure of anything he touches so that he will stimulate a flaw in the Carrier’s metastructure on his next visit to the Carrier.
Ivana Baiul threatens her underlings with sale to Blood Congresses for use as host bodies.
Nate consults an informant Blood Congress on the fate of Gen 13. This particular Blood Congress originally belonged to a Jerome McIntyre whose body exploded during an earlier period of war between factions of the Blood Congress. This Blood Congress has already evolved through twenty-six generations since that time. It declines to aid Nate in containing the destructive forces released by the deaths of Gen 13, as it will not be affected by the catastrophe.