Simon,
    Here's those rise of the triad codes. Type them in the game.
   dipstick-  enables codes
   chojin  - invincibility with weapons. Use INSERT to cycle through them
   goto - lets you pick any level you want
   chase - you follow the missile when you shoot it. Try it.
   dimon - turns lighting on
   dimoff - turns lighting off so you can see better
   london - turns fog on
   nodnol - turns fog off
   flyboy - you can fly. Use the page up and page down keys.
   shrooms - your high
  There is few more but these are all I know.:)
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