Copyright (c) 1999 Gary Wong

The game is played on a initial empty odd-size square board (let's say 9x9).

FIRST STAGE - Each player, in turns, drops N-1 stones into empty cells (with a NxN board).
SECOND STAGE - Each player continues to drop stones into empty cells, but now, each stone must have two or more adjacent (orthogonal or diagonal) friendly stones.
GOAL - The last player to move wins.

Another way to define victory is to state that when both players pass, wins the one with more stones on the board.

An example

The first stage has ended, both players had dropped 8 stones into a 9x9 board.

Cell [1] is valid for both players, cell [2] is not valid for either player!

Ralf Gering tried the game: It's quite Go-like in the way it feels and influence plays an important role. [...] Wong's Game played on 15x15 needs about 4 Komi for White to balance Black's first move advantage.