RHEM 2 is an adventure game from Knut Müller and Got Game Entertainment and the sequel to RHEM. It is distributed as a Macromedia Director file.
Like Myst and Riven, Rhem 2 is a node-based first-person adventure game. The player explores a series of caverns in search of a certain artifact. The puzzles involve spatial reasoning, operating machinery, and logic.
There is little plot or character interaction in Rhem 2; the emphasis lies solely on its puzzles. Many puzzles require the player to determine his location with respect to adjacent areas or objects in order to solve it. For instance, in order to solve a puzzle it may be necessary to trace a cable through a wall between two rooms, but the path from one room to the other is circuitous.
Source: Wikipedia, "RHEM 2: The Cave", available under the CC-BY-SA License.