Listing of games available:6

X-Car 
X-COM:Apocalypse
XS
Xargon
Xenon 2
XenoPhage
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X-Car:

Use these cheats during a race.

Code           Description
Ctrl Shift F8  Changes map color.
Ctrl Shift F9  Repairs damage.
Ctrl Shift F10 Clears black flag

At the track selection menu, while selecting a track, hold down s to get
sunny weather or r for rainy.
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X-COM:Apocalypse

Load a non-tactical mission game file in a hex editor, such as Hex
Workshop. At offset 33D40, type in FFFFFF to get lots of credits.

The following only works in the beta version. To activate the cheat
mode in X-COM: Apocalypse Cityscape, hold down Alt while typing
"ufo cheat". If successful, the message bar will tell that the cheat mode
has been activated. If it doesn't work, press Alt and any other key than
u. Then try again.

Code                      Description
Alt Keypad +              One item of everything.
Alt 0 1 2 3 4 5 6 7       Flips dimension.
Alt a                     Toggles auto-save.
Alt b                     Base mission.
Alt c                     Forces UFO to crash.
Alt d                     Toggles dimension map cheat.
Alt f                     Toggles build base facilities cheat.
Alt g                     Test alien dimension.
Alt m                     $100,000.
Alt n                     Number of aliens in buildings.
Alt p                     Finish project instantly.
Alt q                     Allows manufacturing anything.
Alt r                     Allows researching anything.
Alt s                     Forces overspawn.
Alt t                     Forces apocalypse mission.
Alt v                     Toggles view the whole ufopaedia.
Alt x                     Gives you one of each vehicle.
Alt z                     Shows all people tube connections.
Alt Esc                   Disables cheat mode.

To activate the cheat mode in X-COM: Apocalypse Tactical, hold
down Alt while typing "tac cheat". The message bar will tell you if it
worked. If not, press Alt and any other key than t. Then try again.

Code                      Description
Alt f                     Increases musical intensity.
Alt g                     Decreases musical intensity.
Alt h                     Toggles hidden terrain.
Alt i                     Toggles God mode.
Alt k                     Kills all hostile units.
Alt r                     Shows frame counter.
Alt t                     Toggles training mode.
Alt v                     Toggles hidden units.
Alt w                     Toggles weightlessness.
Alt Esc                   Disables cheat mode.                              ----------------------------------------------------------------------------
XS:

Use these cheats as your name at the Login screen in XS

Code       Description
Alicat     Changes characters into cats.
Chicken    Play as a penguin.
Fishfort   Changes characters into penguins.
Hungry     Changes characters into hippos.
Medical    Secret Underworld level.
Muddy      Play as a hippo.
Pension    Secret Freezer level.
Slither    Changes characters into worms.
Smelly     Play as a cat.
Wriggle    Play as a worm.
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Xargon:

During the game, press F7 three times.  This will bring up a 
cheat menu.
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Xenon 2:

When the game starts, you must select a graphics adapter
and press enter. Instead of enter, press F7.
When playing, Press letter  i  and you will be in GOD mode.
Press i again and you are in normal mode.
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XenoPhage:

Type in the cheats while playing XenoPhage, unless otherwise is stated:

Code         Description
Shareware or Registered
bishop       Voice message: "YOU SUCK!".
blood        Increases the amount of blood.
glassjaw     Fighters stun each other.
helium       Jump higher and come down slower.
invisible    Both fighters become invisible.
shadows      The bodies of both fighters disappear.
stain        The blood stains the ground.
thoughtjinx  Both fighters fall down and die.

   Registered Only
blarney      Fight the secret fighter, Blarney! Any menu.
champs       Select any one of the 3 boss fighters. Menu.
orchid       Selena stiffens and blossoms and grows.
xacman       XacMan: a mini-game within XenoPhage. Menu.
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