Moria is an ASCII-based roguelike developed by Robert Alan Koeneke and Jimmey Wayne Todd Jr. for the DEC VMS operating system in 1983. It casts the the player in the role of a novice adventurer, who must fight their way down to the 50 levels of the Mines of Moria to finally defeat the Balrog to win the game.
The game was under active development throughout the 80s, and became the first major roguelike to be open sourced, allowing ports and variants on platforms like Unix, Acorn 32-bit, Amiga, Atari ST, PC (DOS), and Mac. But as the creators stepped away from the game in the 90s, interest in it declined and the last official release was in 1994. Its heritage still lives on in Angband however, which was largely based on Moria and continues to be actively developed today.