der_Riese is a custom map for Insurgency: Sandstorm, designed for Windows. This map introduces players to an underground research facility, where the objective is to liberate the area from terrorists. It features multiple game modes, including Checkpoint_Security, Survive, and Team Deathmatch, providing a diverse gameplay experience. Players can engage in various scenarios with different lighting settings, enhancing the map's dynamic atmosphere.

The map supports server start parameters that allow customization of gameplay conditions, such as day and night lighting options for each mode. While the creator acknowledges ongoing development, including plans for custom sounds, some known issues persist, such as ground glitches and missing sounds. Overall, der_Riese offers an engaging addition to the Insurgency: Sandstorm experience with its unique setting and gameplay variety.