Null-A Three

Nobody, apparently, can kill Gilbert Gosseyn, who has an extra brain and has already used it to save the Solar System. Van Vogt introduced him in The World of Null-A, built on General Semantics, and closes the series here with a showdown against the originators of cosmic civilization. It was a DAW original, July 1985. Tim Jacobus set Gosseyn over a chessboard.