Dealspwn: 'Typically, games have often revolved around two opposing sides - from the basic binaries of left and right in Pong to epic titanic battles between gods and men and other creatures, the grandeur of warfare, struggles between good and evil, super spies and seedy government organisations. But the industry isn't just restricted to rivalries between characters. The nature of gaming is such that entire series become bound up in the raging battle for approval. Publishers go to war against one another, and then, of course, there are the fans themselves. We are a so often a fairly fickle bunch. Rivalries are part of the business, so here are ten of the best.'