The player commands a German U-boat from a first-person interior view. Navigation, chart reading, visual spotting, periscope use, sonar interpretation, depth control, and torpedo firing are central tasks. Surface travel is faster but exposes the submarine to aircraft and surface ships, while submerged movement improves concealment at the cost of battery power and speed.

Missions are organized around patrol objectives and historical operations. The commander searches for targets, chooses an attack position, launches torpedoes, manages damage and supplies, and decides when to disengage. A career campaign tracks patrol results and progression, while individual missions and training provide more focused scenarios.

Plan attacks before exposing the submarine. Use the chart, range information, and target course to estimate a firing solution rather than launching immediately.

Remain submerged when aircraft or escorts are nearby, but monitor battery power and air availability. After an attack, change depth and bearing, reduce noise when possible, and leave the area instead of waiting for every torpedo to hit.

Protect the boat’s long-term career. Repairs, ammunition, fuel, and crew condition affect later patrols, so a successful withdrawal is often better than pursuing a damaged target into an escort screen.