Paradox Interactive is best known for developing historical grand strategy games, almost exclusively for PC. Their most popular franchises include Europa Universalis, Hearts of Iron and Crusader Kings. Since 2012 the game development is handled by there internal arm (Paradox Development Studio). In recent years, Paradox has also become a major publisher of third-party games, such as the Mount & Blade and Magicka series, War of the Roses, Knights of Pen and Paper, Cities: Skylines and Pillars of Eternity.
Most recent Paradox-developed games are based on the company's proprietary Clausewitz engine, introduced in Europa Universalis III. Paradox also began licensing out its earlier Europa Engine for free.