Boulder Dash (1985)

Boulder Dash is a maze-based puzzle video game released in 1984 by First Star Software for Atari 8-bit computers. It was created by Canadian developers Peter Liepa and Chris Gray. The player controls Rockford, who tunnels through dirt to collect diamonds. Boulders and other objects remain fixed until the dirt beneath them is removed, then they fall and become a hazard. Puzzles are designed around collecting diamonds without being crushed and exploiting the interactions between objects (such as a butterfly turning into diamonds when hit with a falling rock). In 1985 an arcade version was released on Data East's "DECO Cassette System", with improved graphics but a reduced display grid on a vertical monitor.