Abstract: A game piece with a hidden image that is visible through a decoder filter, with a first visible layer having an image gradient mapped to a first electromagnetic wavelength range and a second visible layer with a disguising mask and the image gradient mapped to a second electromagnetic wavelength range, the electromagnetic wavelength ranges selected based on a color hue for the decoder filter and the disguising mask having an electromagnetic wavelength within the second electromagnetic wavelength range. A method of making a game piece with a hidden image that is visible upon viewing through a decoder filter is disclosed.

Abstract: An interactive electronic game system is provided. The game system comprises two or more gaming machines each having display means for displaying images thereon and interaction means for an individual player to interact with the game system. A central server unit comprising a game system control means and a communication control means for controlling communications between the central server unit and the gaming machines is provided. A network connects the gaming machines to the central server unit. A random number generating means connects to the central server unit. The central server unit is arranged to play a game in which two or more players select one or more sub sets of indicia from a set of indicia. The selected sub-set is displayed on the display means of each player's respective gaming machine. The random number generating means generates a sequence of random indicia selected from the set of indicia.