This article provides step-by-step instructions about how to create a simple, yet interesting, augmented reality game called “domino knock-down game” using an open source framework called Goblin XNA.Introduction This is an advanced tutorial, and as such we expect that you are already familiar with XNA and scene graph based 3D programming. The game is a single player game in which the player shoots virtual balls into a real-world environment to knock down all of the virtual dominos overlaid on top of a board. The player holds a webcam in one hand and shoots the virtual ball by clicking a mouse using the other hand. Before the game starts, the player is allowed to add virtual dominos or modify the positions and orientations of the existing ones overlaid on the board as desired. Read more: Coding4fun