If you have played Silent Hunter 3 you know what this is all about. Gameplay-wise there is not much difference between this (Silent Hunter 4) and Silent Hunter 3. But graphics have been improved and time can be compressed even more than in SH3 because of greater distances to travel (after all this is set in the Pacific Ocean!) Unfortunately, you do not get to be the bad guys this time. This time you control an american submarine (Gato, Tambor, Sargo etc.) in the time period 1941-1945. You decide yourself if you want this to be a pure U-Boat simulator or a "U-Boat arcade game", by adjusting the realism-level. 100% realism means no external camera-view, limited oxygen and batteries etc. You will have to live and act like a real submarine-captain. While 0% realism means full external camera-view, unlimited oxygen and batteries etc. You can also choose anything between 0% and 100% realism. Like full external view but limited oxygen. If you choose campaign-mode you will be assigned with different missions. Usually it will be to patrol a certain grid on the map for 24 hours, and you are bound to encounter some enemy ships along the way (usually japanese). The more enemy ships you sink, the better, and the more medals you will receive. The greatest feature in this game, as far as i'm concerned, is the stunning graphics. The water is even transparent (unlike in SH3), and looks just like it does in real life. I personally like Silent Hunter 3 better because I think there is overall a better atmosphere in that game, but I have to admit that watching Yamato appear on the horizon in front of the red sun is a pretty awesome sight. The great musical experience from SH3 does continue in this game.