Missions are devided in 7 stages, that goes form "A" to "G", and about 80 missions, including the Special Missions, and the Hidden Missions, in all of them is a diferent kind of enemy ships, with different weaponry, and more and more powerfull. for exemple, from stage A to C, enemy Ships still be weak to cruisers, but from D to E, The cruisers have more trouble, and from F to G, the last 2 stages, enemy fleets start to use High tech guns, like lasers and have more armor than usual ships, and start to appear Powerfull battleships, that uses Anit-Ship missiles and lasers, and submarines that uses missiles and high velocity torpedoes, from stage D, its recommeded to use a battleship, and develops Electromagnetic And Gravitational Shielding, also to start to develop better escorts, becouse escorts make you have an "S" rank, in all mission stages there is a final boss, like all games, this is the list of those Flagships
G-10-----Druna Skass 2
--Hidden bosses appears in the stages A* to G*, there is a difference between A* and A
--The Wave Gun its a pick up weapon, you can find it in the mission when the Super U.F.O appears or one mission before that.
--The missions A-6 and A-a are real battles from the WW2