First released in 1984, the game received excellent reviews and went on to spawn numerous sequels, conversions, and clones. You guide a little man called Rockford up, down, left, and right through scrolling caverns of boulders and diamonds. Your aim is to collect a set quota of diamonds within a time limit and then reach the previously concealed exit. Boulders can be pushed or dropped by digging through the earth that supports them, but it’s all too easy to be hit by a falling boulder, miss out on necessary diamonds, or bury the exit under an avalanche.