Type debugon during game play to enable debug mode. Dinosaurs will ignore your character until you shoot, weapons will have unlimited ammunition, and lava is not harmful. Additionally, enter one of the following codes to activate the corresponding cheat function.
Run very fast [Ctrl]
Toggle slow motion [Shift] + S
Toggle frame rate and polygons per frame display [Shift] + T
Longer jumps [Ctrl] + N
Display time [Ctrl] + T
Full map [Tab]
Hold before entering water to swim [Space]
Press [Walk] + [Jump] while in deep water to swim.
Tyrannosaurus Rex: In most cases, the Sniper. However the X-bow can be used to kill one right on the edge of the viewing area.
Velociraptor: Usually Shotgun, sometimes X-bow.
Allosaurus: Usually X-bow, sometimes Shotgun.
Triceratops: Usually X-bow, sometimes Sniper.
Stegasaurus: Either X-bow or Shotgun.
Pachycepholasaurus: X-bow or Sniper.
Parasouralaphus: Any weapon.
Dimorphidon: X-bow, or Sniper if skilled.
Brachiosaurus (hidden): X-bow only. It repels anything else. Target the rear.
Seismosaurus (hidden): X-bow only. It repels anything else. Target the eye, it is is about 1/7 the size of the T-Rex's. After releasing it, run quickly to the nearest anti-Carnivore mountain!