Kensington is a really great late 70s game for two. Invented in 1979 by Brian Taylor and Peter Forbes, it was sold in an LP sleeve, and its space-age board would have looked right at home as a prop on Blakes 7.

The black-coloured board is covered in a pattern of fluorescent green lines, joining 72 vertices into a pattern of triangles, squares, and seven coloured hexagons (three white, two red and two blue).¹

Each of the two players, Red and Blue, has 15 pieces. The object is to capture
a hexagon of your own colour or one of the white hexagons by filling all six
vertices with six of your pieces.

Initially, take turns to put a piece on any free vertex on
the board. Once all pieces are in play, each turn move one piece along an edge
to any adjoining free vertex.

Now for the trick. If by placing or moving a piece you capture a triangle, you
can reposition any one of your opponents pieces to any free vertex on the board.
Capture a square to reposition two.

An 'optional' rule provides that you cannot recapture a triangle or square you have just released without waiting a turn. Without this rule the game is very unforgiving of any mistake in play, so in practice it is almost always used.

Four and six player versions do exist, but they are simply partnership versions of the two-player game.

As the sleeve says, 'Simple to Learn, A Lifetime to Master'. Your life
is getting shorter by the minute, so begin now!