Arma

The 'Arma' series by developer Bohemia Interactive is a collection of military simulations. Arma is known for its realism, extensive content, vast maps based on real-world locations, and a large modding scene. Notably, Arma 2 is the direct predecessor of DayZ. Arma offers massive battles with hundreds of players across various epochs, as well as co-op missions and a single-player campaign.