XOR (video game)

Infobox VG| title = XOR


caption=
developer = Astral Software
publisher = Logotron Ltd
designer =
engine =
released = 1987
genre = Puzzle game
modes = Single player
ratings =
platforms = ZX Spectrum, Commodore 64, Amstrad CPC, Amiga, Atari ST, Acorn Electron
media = Floppy disk, audio cassette
requirements =
input = Keyboard, joystick

"XOR" is a computer puzzle game created by Astral Software and published by Logotron in 1987 for a range of platforms including the Acorn Electron, Amiga, Amstrad CPC, Atari ST, BBC Micro, Commodore 64, and ZX Spectrum. It has since been remade for platforms including Windows, Apple Macintosh, RISC OS and Game Boy Advance.

"XOR" is a pure puzzle game with no random or arcade elements, as summed up by the blurb on Logotron's original extensive advertising campaign::"There are no random events in XOR's labyrinthine palace, and there is no premium on hand-eye coordination. You have all the time in the world to work out the precise nature of the hazards you encounter. Logical thinking, strategy and tactical problem solving are part of the XOR experience. And XOR is not simply about finding solutions. If you can solve the entire puzzle (15 levels plus an encrypted anagram), you qualify to be a member of the Order of XOR."

Gameplay

Objective

The player controls two shields, "Magus" and "Questor", which can be moved horizontally and vertically though the maze, in order to collect masks. The object of each level is to collect all the masks, then reach the exit. In all levels, both shields are required for completion, and in some, one shield must be sacrificed (walled in or destroyed) in order to complete the level.

Force fields

In the first level, the only obstacles except for the maze walls themselves, are two types of force field: one of which can only be entered from above or below, and a second which can only be entered from left or right. In both cases entering the force field destroys it.

Fish and chickens

In subsequent levels, fish and chicken objects are introduced. Fish fall downwards whenever possible, while chickens run to the left if not blocked. Both can destroy the player's shields if they hit it from more than one square away (like rocks in Boulder Dash). Fish and chickens can move through force fields if entering from the appropriate direction.

Bombs

There are two types of bombs in XOR: V-bombs ("vertical") and H-bombs ("horizontal"). V-bombs (shaped like jars of nitroglycerin) move left in the same manner as chickens, while H-bombs (shaped like old-fashioned spherical bombs with a burning fuse) fall downwards like fish. However, unlike fish and chickens, H-bombs and V-bombs can be pushed by the player's shield, upwards and rightwards respectively.

A bomb explodes when it is hit from more than one square away by a fish, a chicken, or another bomb. The object hitting the bomb is destroyed, along with anything directly above or below a V-bomb, or to the left or to the right of an H-bomb. If one bomb hits another, only the bomb that is hit (the lower or left-hand one) actually detonates.

Dolls

Unlike fish and chickens, dolls cannot move on their own, although the player's shields can push them around the maze. Once a doll is moving it keeps going until it hits an obstacle. Dolls cannot detonate bombs or pass through force fields.

Other objects

* Map sections: these reveal the layout of part the maze to the player. Masks are highlighted on the map.
* Frowning masks: these are switches - collecting (or blowing up) one turns off the lighting, causing the maze walls to become invisible, while collecting another turns the lights back on again.
* Teleportation portals: this moves the player's shield to the other teleportation portal within the maze.

External links

* [http://xor.ovine.net Windows remake] by Ovine by Design
* [https://rvvz.home.xs4all.nl/xor/ JavaScript version by Rob Veldhuyzen van Zanten]
* [http://www.gbagames.dsl.pipex.com/xor_home.htm Game Boy Advance remake by Mick Waites]
* [http://www.danceswithferrets.org/xor/index.htm "XOR" information site] including RISC OS version for download.
*WoS game|id=0005800|name=XOR