9. Real-Time Strategy - Dune II
During the 1990s, real-time strategy games like Starcraft and Command and Conquer exploded in popularity. Warcraft often takes the credit for redefining strategy games, even though that honour belongs to Dune II: The Building of a Dynasty, which came out a year earlier.
Although 1981's Utopia set the template for RTS gaming, it was Dune II which popularised many core concepts synonymous with the genre. It focused on base creation, resource-gathering to fund constructions, building construction dependencies, deployable mobile units, army micromanaging, and factions with unique units and weapons. Simple ideas like using the mouse to drag units from A to B were devised in Dune II long before they became a staple in the genre.
Like Citizen Kane, Dune II didn't invent these concepts, but it was the first game to mesh them together cohesively. Although games have evolved massively over the years, the core mechanics of modern real-time strategy titles has remained virtually unchanged from Dune II, since its system can't really be bettered.
Even though Frank Herbert's Dune novels are revered for influencing the sci-fi genre, we must never forget how his work also reshaped the real-time strategy genre.