All these cheats are selected in pause mode with the following keys,
regardless of the keyboard/mouse configuration.

                  R = Right cursor key
                  L = Left cursor key
                  U = Up cursor key
                  D = Down cursor key
                  E = E key
                  A = A key
                  O = O key


                  DH1
                  REDO -- 50 grenades, all types
                  RUDE -- Invulnerability
                  REED -- Fat people
                  DEAD -- Floating corpses
                  REAR -- Reverse controls
                  OOEER -- Plants scream when shot
                  AAAAAAAAAARRRR -- Skeleton mode
                  DOODAD -- Silly animations
                  DEER -- Silly voices
                  RUDDER -- Change weapon + infinite ammo


                  DH2
                  RELOAD -- Lots of grenades
                  ODDEXE -- Fergality
                  DEAD -- Skeletons
                  DARE -- Immortal
                  RUDE -- Reload to any gun

                  DH3
                  "RUDE," DataOn -- On-screen data
                  "DODOR," UseAllCams -- Allow Freedom camera
                  "ODDAXER," ShowFergus -- Fergus mode
                  "LULLEDA," SlowMeDown -- Run super smooth
                  "LEADER," LoadsAPlanes -- 16 planes on city levels
                  "OOEEDDXXR," LoadsATurbos -- 99 turbos
                  "LOUDER," InfLives -- Infinite lives
                  "LARD," FatMode -- Large models
                  "LOROEAXAR," JumpLevels -- Allow warp to different levels