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Exile (arcade adventure)

Exile is a computer game originally published for the Acorn Electron and BBC Micro in 1988 by Superior Software and later ported to the Commodore 64, Amiga, CD32 and Atari ST, all published by Audiogenic. There were both OCS (1991) and AGA (1995) versions of Exile for the Amiga. It was considered at the time to be cutting edge and pushed the boundaries of what was possible on home computers at the time - particularly on the 8-bit platforms. It remains probably the most complex game available for the BBC Micro. Exile's content qualifies it to be the first game to have a complete physics engine.

The game was designed and programmed by Peter Irvin (author of Starship Command) and Jeremy Smith (author of Thrust). Amiga Power magazine voted the OCS version to be the best game of 1991. The multi-format magazine Edge posthumously awarded it 10 out of 10, together with only 2 other games.

Story

The player takes the role of Mike Finn, a leading member of a space-exploration organisation called Columbus Force, who has been ordered to the planet Phoebus as part of a rescue mission. Finn is tasked with abetting Commander David Sprake and the surviving crew of the disabled Pericles ship from a psychotic renegade genetic engineer, Triax (the Exile of the game's title), who appears briefly at the very start of the game removing a vital piece of equipment called a Destinator from Mike's ship, the Perseus. As with Elite, a novella (written by Mark Cullen, with input from the game's authors) was included to set up the story, and to provide some clues as to the nature of the planet Phoebus' environment.

Game Mechanics

The game contains other characters to interact with as well as a physics model with gravity, inertia, mass, explosions, shockwaves, water, earth, wind, and fire. Energy is required to power the weapons and jetpack system, and needs to be collected throughout the game. Finn cannot die: when he reaches a point near death he is automatically teleported to safe locations previously reached and designated by the player, and ultimately back to his orbiting spaceship: consequently in many cases it is still possible to complete the game.

A major feature to this game is the enormous and detailed world it offered for exploration. This is achieved by generating the majority of the caverns and tunnels from a compact but highly tuned pseudorandom process - recreating the same world from the same seed each time - augmented with a few custom-defined areas. This structure was explained in the plot as the crew of the Pericles having set up a base in a natural cave system, with Triax having his own base in caves deep below.

Exile's programming featured innovative routines like creature strategy code that knew about noises nearby, line-of-sight vision through the divaricate caves and tunnels, and enemy's memory of where the target was last seen, etc.

Hardware limitations

The standard 32 KB BBC Model B version used a specially defined screen resolution (8 physical colours; 128 pixels across × 128 lines down = 8 KB screen memory), smaller than full screen MODE 2. The purpose of this was to free up more RAM for the game data. This was a common technique in complex BBC games.

The simplified video hardware found in the Electron did not support this technique, so the additional data remains visible around the screen border. For speed reasons, the Electron version's screen had only 4 physical colours. It did however boast a slightly larger view window of 128 pixels × 192 lines down.

In the case of a BBC Micro computer that had been upgraded with a 16 KB page of sideways RAM, Exile detected this and the option of playing an enhanced version of the game was presented to the user. These enhancements included sampled sound effects and digitized speech ("Welcome to the land of the Exile." and "Alien die!"), as well as a larger visible screen area (8 physical colours; 128 pixels across × 256 lines down = 16 KB screen memory).

The extreme measures taken in fitting the game into a standard BBC micro meant that the main game had no on-screen status indications or text of any kind, or even load and save routines. Fuel and energy levels were sounded out by a series of chimes when a weapon was selected, and pocket contents could only be checked by putting items back into Mike Finn's hands to make them visible. Despite such measures being forced by necessity, they very much formed part of the character and appeal of the game. Saving the game entailed pressing a shutdown key, resetting the computer, and launching the loader programme again.

Game Locations

Aside from the Perseus and Pericles ships, the world of Exile has many cave systems and tunnels. These locations in approximate order of depth are:

Aurora, Honeycomb, Lyre, Eridanus, Amaranth, Rune, Hamlet, Inferno, Sarawak, Puck, Nemesis, Orotund, Bigwig, Waters, Sulaco, Artesian, Carrion, Eclipse, Gemini, Madrigal, Zephyr, Pogrom, Drey, Behemoth, Yarrow, Nebulous, Loganberry, Laager, Ferro, Askance, Aquila, Nidus, Blackdown, Abscond, Diapason, Agamen, Vendetta, Scorpius, Brazil, Okhotsk, Tutelary, Eros, Palermo, Aeolus, Esplanade, Fury, Antipodes, Hades, Eyre, Pascal, Hydra, Hercules, Cassandra, Cetus, Triton, Acheron, Zeppelin, Kielder

Miscellanea

Cheat programs were created that took advantage of the object system of the game, allowing the character to fire, in addition to the standard bullets, boulders, grenades, and even clones of himself. Also of note was Exile's copy protection routines, noted by some for their ingenuity, although this has since been defeated and was 100% cracked by Galahad / Fairlight.

Authors

Jeremy Smith died in a tragic accident several years after Exile was published. Peter Irvin is an active game developer.

William Reeve executed preliminary conversions of the BBC Micro game to the Amiga and Atari ST. These were then upgraded and completed by Peter Irvin and Jeremy Smith.

Tony Cox did a preliminary conversion of the game from the Amiga to Amiga CD32.