Die Seehunde

From BoardGameGeek:

Die Seehunde is a tactical-level wargame playable in solo or Co-operative modes. You, the player, will be in command of a single German midget submarine in the last months of World War 2 in 1945. The game can optionally be played with a second submarine, either Co-operatively with a friend or, for solo players, by controlling both submarines yourself. By sinking enemy shipping, your overall goal is to score as many Victory Points as possible, and, more importantly, stay alive. Gameplay is divided into different phases which represent specific time frames and situations. Being the starting point of most single mission scenarios, the Sortie Phase represents your journey to the mission area. Each round, which represents roughly 12 hours, allows you to move closer towards your objectives, or just to the nearest convoy route in the search for prey. If your submarine has sustained damage, it's also possible to carry out rudimentary repairs. Once you have found a convoy, or you have been found by its escorts, the Encounter Phase takes over on the Tactical map. It represents a section of the open sea, which is centered around the enemy force, namely the convoy or a group of escorts. Time in this phase is abstracted and relative, with each round representing approximately 2-8 minutes. Patient observation followed by keen torpedo attacks is the core experience of Die Seehunde. For players seeking the full campaign experience with multiple sorties, the Campaign Phase simulates your time spent at the harbor base between missions. Here you are able to repair your submarine, heal your wounds, or simply relax from your exploits at sea. With a time scale of 1 day, random events will introduce missions, challenges, and opportunities for you to master, until it is once more time to set sail. The game features six types of submarines: two variations of the original Seehund ("seal") (standard Seehund and Seehund mod.), one predecessor in the form of the Hecht (“pike”), one fictional successor in the form of the Seehund II, and two special submarines - the Elektro- boot (“electric boat”) coastal submarine and the Marder (“marten”) human torpedo. The Elektroboot and the Marder can only be played in special scenarios or skirmishes and are not available in the campaign.