FLY - You can fly around.
GHOST - Let's you walk through walls.
GOD - Can't get hurt.
WALK - Returns you to walking mode if you are flying or ghosting.
INVISIBLE - Guess. (Invisibility).
KILLPAWNS - Kills all monsters.
WALK - Turns off "GHOST" or "FLY".
SLOMO # - Slows or speeds up the game.
SUMMON - Lets you add a weapon or an item to the world.
PLAYERSONLY - Freezes time (Press again to resume time passage).
OPEN MAPNAME - Jump to any map, just need to enter the name like OPEN DIG.
FLUSH - When you start getting odd graphics on wall textures or creatures, type this in order to fix it.
BEHINDVIEW 1 - Puts you in a Tomb Raider style of view.
BEHINDVIEW 0 - Resets this.