Players take turns adding 12 tiles of their own colour to form a single connected board. They then take turns removing tiles of their own colour. If the board is split into more than one group, the largest group only is retained. The first player to remove all of their tiles from the board wins.

Halves may be played on gamerz.net:

http://www.gamerz.net/pbmserv/List.php?Halves

and is fully described on the designer's web site:

http://cameronius.com/games/halves