A significant quality-of-life automation feature was added. Players can now click a single button to have the boat automatically dive to an optimal depth, stay for five minutes while the radioman listens for contacts, and then surface to replenish air.
The (released as the "Christmas Update") introduced several "deep" features focused on immersion, automation, and expanding the game's theater of operations. Key Deep Features in B131
Heavily armed German warships now occasionally accompany you, particularly during Mediterranean missions. UBOAT Free Download (B131)
Water now realistically affects the camera view.
The periscope interface was completely overhauled to be more intuitive, including built-in video tutorials for each tool. A significant quality-of-life automation feature was added
A new HUD element was added to provide immediate awareness of nearby contacts, mission objectives, and ports.
Periscopes now leave a visible wake while moving. Key Deep Features in B131 Heavily armed German
For more details, you can view the official B131 Update Trailer or read the full patch notes on SteamDB . UBOAT - Christmas update: B131 - SteamDB