Access Secret Ships:
     Secret ships press tab+1 or tab+2 during the game.

Skip Level:
     Press F3, F6 and F7 during the game.

All Super Arcade Modes: 

The Experimental PQZ ship: Type 'TECHNO' at the Tyrian 2000 main menu.
TX Silvercloud: Type 'UNKNOWN' at the Tyrian 2000 main menu.
Stormwind - The Elemental: Type 'STORMWIND' at the Tyrian 2000 main menu.
Ninja Star: Type 'STEALTH' at the Tyrian 2000 main menu.
Foodship Nine: Type 'WEIRD' at the Tyrian 2000 main menu.
Dragon: Type 'LIZARD' at the Tyrian 2000 main menu.
Captured U-fighter: Type 'ENEMY' at the Tyrian 2000 main menu.
Pretzel Pete Truck: Type 'PRETZEL' at the Tyrian 2000 main menu.
Nort-Ship Z: Type 'NORTSHIPZ' at the Tyrian 2000 main menu. 

Hidden difficulties: 
     On  the difficulty selection menu, press 'SHIFT' and 'G' together
to open the Impossible setting.

     After  entering the code for Impossible setting on the difficulty
selection menu, press 'SHIFT' and ']' to open Suicide setting.

Super Tyrian mode: 
     At the Tyrian 2000 main menu, type 'ENGAGE' for Super Tyrian mode
Lord of the Game difficulty.

     For Super Tyrian mode on Suicide difficulty, hold the Scroll Lock
key and type 'ENGAGE' at the Tyrian 2000 main menu.

Debug mode: 
     During a level, press 'BACKSPACE' and 'F10' to enter/exit debug mode.

Invulnerability: 
     During a level, press 'F2' + 'F3' + 'F6' together. If the message
"Cheaters  always prosper" appears, you've entered the code correctly.
You  can  lose  all  of  your  armor,  but  you will not die until you
deactivate the code (by pushing 'F2' + 'F3' + 'F6' together again).

Random Color Change: 
     During  a level, press 'BACKSPACE' and '-' to randomly change the
board's color scheme.

Random Song: 
     During  a  level, press 'BACKSPACE' and 'SCROLL LOCK' to randomly
change the background music.

Christmas mode: 
     From  the Start-Programs menu, select "MS-DOS Prompt". A DOSshell
window  will  appear. Change to the Tyrian 2000 folder. Type "file0001
yesxmas"  and press the 'Y' key when prompted. Certain items, weapons,
ships and sound effects will be changed to reflect the holiday spirit.

Destruct Mini-game: 
     Type  'DESTRUCT'  at  the  Tyrian  2000  main  menu to access the
Destruct mini-game.

There are five modes to play:
5-Card War (5 units vs 5 units)
Traditional (one on one battle)
Heli Assault (4 helicopters vs 8 ground units)
Heli Defense (8 ground units vs 4 helicopters)
Outgunned (green troops outnumbered by opponent's units)
Press 'F1' for the list of controls. 

Instantly end level: 
     During  any level, press 'F2' + 'F6' + 'F7' to instantly warp off
of  the  level.  Please  note  that  this will not work with any Super
Arcade ship nor will it work in Super Tyrian mode.

"Super" Pause: 
     During  a  game,  press  'Backspace'  and 'Number Lock' together.
After doing this, you will not see the word "Pause" on the screen when
you pause the game (by pressing 'P').

Wild Detail mode: 
     Run  the  Tyrian  2000 setup program. Highlight "Game Detail" and
press the 'W' key.