Clade

The Clades were once simple weapons but then scientists went too far and the Clades learned to think for themselves. Subsequently, they took up the mantle of "peacemakers" and went after Alvin Godlove, who they controlled. Later they controlled the Doctor, but the Doctor was able to kill the two Clades on Earth. While the Doctor was able to kill those two, others may still be alive elsewhere. (TDA: Peacemaker)