Dark omen is a one of those game that you can't stop playing even if you lose over and over again.
With a very good story and a superb voice acting you go though 25 missions.
You start with a few troops but later they will join you more, you have mages, ogres, elfs and so on.
You gain gold and items in some missions and with that gold you can upgrade your troops or buy reinforcement for some unit.
The game is hard very hard some mission will take you several tries to beat them and if you lose an unit you can continue the game but is not recommendable because you will need them later, so one unit lost restart the level.
You need to use strategy very well and thats the point where the game shine, is hard yes but if you do the things right you can beat every mission even if it seems impossible every mission is beatable.
Not everything is good, the controls are not the best, you can't move the camera with the keyboard something essential in a real time strategic game, you can't change the key binds, cant select more than one troop at the time.
The gold is very scarce and you will often wont have enough to buy reinforcement so sometimes the game is way to hard with no reason this and the bad controls make it more hard than it should anyway the game is great even with it flaws.