This prototype was found at a flea market in Eindhoven in the Netherlands, by Dutch collector Marco Kerstens. The game is the same as the Clay Pigeon that was released in Brazil except that it contains high-resolution background graphics when played on a G7400 or compatible console. The Brazilian version contains no such background graphics; interestingly however, the background scene on the Brazilian box/manual cover as the same as the background graphics in the European prototype.
Some detailed documentation was found with the prototype, indicating that Philips planned to release Clay Pigeon in Europe with Videopac number 56. They never did, however, and instead released Norseman with that number.
French collector Nico "sap1" Sapin released reproduced copies of Clay Pigeon +, complete with authentic looking cartridge labels, box inserts, and a manual based on the prototype documentation. Nico assigned Videopac number 62+ to the reproductions. Only 15 cartridges were produced by Nico.
Cartridge copies of Clay Pigeon + were re-issued by Humanoid Games at a later date.