- You may be looking for the television serial or Rondel, a guard from Vengeance on Varos.
Rondel, known anciently as the Arc of Infinity, was a region of space devoid of all stellar activity, formerly the location of a collapsed Q star. It was known as a curve between dimensions. Due to the burnt-out Q star, it was possessed of great quantities of quasi-magnetism, which helped shield the anti-matter Omega. He therefore used the region as a "home base" of sorts, from which he gained entrance to his native, "positive" universe. (DW: Arc of Infinity)