Players play metal tubes of varying sizes onto one of three building spaces. Added in are six thin wooden columns, which only remain visible when their tips can still be seen over the topmost edge of the metal tubes. Each player has components in a single color, but both players can use the tubes and columns of his opponent. See and be seen - only that counts at the end of the game. The player whose building materials can be seen the most at the end of the game is the winner. San Ta Si is a spatial hide-and-seek game for thinkers who love to build.