Supaplex

Supaplex is a video game created by Philip Jespersen and Michael Stopp, two Swiss students, and published by Digital Integration in 1991. It is an extended clone of Boulder Dash.

Aiming to develop a version of Boulder Dash that could fit onto a floppy disk, the designers had a hard time developing better graphics under said constraint. The original Amiga Supaplex version had to fit on a standard 880 kB floppy disk and needed to run on a standard 512 kB Amiga like the original A500 or A2000. In fact, the Amiga version could not be copied onto the hard drive due to copy protection and its custom disk format.

The game comes with 111 levels, though many unofficial level sets have been released that greatly increase that number. Although the levels must be played in order, the game allows up to three levels to be skipped at any given time. Also, it was very easy to skip additional levels by editing the file that contained the list of levels successfully completed. The game is very challenging, but unlike many Boulder Dash-related games, the difficulty comes from solving the puzzles in each level rather than from semi-responsive controls. Furthermore, Supaplex does not use time limits for solving the puzzles, unlike Boulder Dash.

Supaplex introduces a number of new elements that were not present in Boulder Dash, including bugs, pieces of base that randomly cause life-threatening electrostatic discharges, Ports, which limit Murphy's movement to specific directions, and terminals, which set off yellow Utility Disks. Utility Disks are explosive floppy disks and come in three different colors: Orange Disks work like Zonks, but explode when hit or when falling. Yellow Disks do not fall, yet may be pushed in any direction, but not pulled (which allows creating Sokoban-like puzzles), and explode when the Terminal is used. Red Disks can be carried and dropped when convenient, exploding seconds after.

Supaplex is the first Boulder Dash-like game that is not fully grid-based: while the playing field is an obvious grid, the objects do not "snap" from one grid position to another, but can be halfway or "in between" grid positions while moving or falling. This behavior has led to a number of well-known bugs that can be turned to the player's advantage, many of which need to be exploited to complete fan-made levels. For instance, by turning around quickly, the player can cause an enemy or rock to "bounce" off Murphy.

The game also applies "gravity" on some levels, which means that Murphy will fall down empty spaces and will be unable to go back up, unless he climbs up by using bases. Gravity is not indicated visually – the player can only notice by trial and error. (Source: Wikipedia)