Hearts of Iron 2 Complete is a turn-based strategy game that includes the Doomsday and Armageddon expansions, where the player can take control of one of 175 states and develop its policies over many in-game years. The time frame of the game covers the period from the beginning of World War II to its end, and even several years after. The Third World War is already close. You need to be prepared for anything and have time to gather a large enough army to capture other states and protect your own. The ability to properly organize soldiers and allocate resources will play an important role in the survival of the country and will influence the course of history on VE Day II.

The whole point of HoI 2 is military action. You can create an anti-personnel army, control a huge fleet or aviation. With the help of diplomacy, opportunities are opened for concluding alliances with other states. The player controls both politicians and generals, who can be sent on missions. By taking foreign and domestic policy into his own hands, the player will be able to stage a coup and change the country's economy. In addition, the development of the industry will also depend on the actions of the gamer. All resources, both human and traditional, must be managed. A shortage or excess of one of them can worsen the position of the state during the war. The game has scenarios that depict important historical events. And the player will directly participate in them.