Conquest of Elysium 3 is an old school fantasy strategy game. You explore your surroundings conquer locations that provides the resources you need. Resources needed vary much depending on what character you are, e.g. the high priestess need places where she can gather human sacrifices, the baron needs places where tax can be collected and where iron can be mined. These resources can then be used for magic rituals and troop recruitments. The main differentiator for this game is the amount of features and special abilities that can be used. The game can be played on Windows, Linux (x86 and raspberry pi) and Mac OSX (intel and powerpc).
Good, deep gameplay while still remaining accessible. The game can be quite difficult depending on the game settings, regardless of the ai difficulty you choose. Do watch some of the gameplay vids on youtube for the best idea of how it plays as they are very informative.