Cheat Codes
Start the game with the command-line parameter '-redrum -stendek'. Now during gameplay, press any of the following:

F7 : Indestructable Toggle On/Off
F8 : Invisible Toggle On/Off
F10 : Mission Complete AUTO
F11 : Mission Complete MANUAL
F12 : Mission Failed

Buy Any Ship And Weapons
Open up the aquanox/dat/sav folder. With a text editor, open up the file player_start.des In it you can change the amount of credits you start the game with. I used 999999 as my amount and it worked fine. If you try more, it might crash. After all, you will see a warning "Do not modify" at the top of the file, so don't get greedy. This amount will carry over into the missions as you progress. You can buy any ship and weapons that are available.

Choose your starting Submarine
NOTE/Disclaimer: This code requires editing a file, I strongly recommend you make a backup of it first. You have been warned. Don't blame me if anything goes wrong.

To do this, go to My Computer, double-click the harddrive on which Aquanox is installed and follow: Program Files/Aquanox/dat/sav. You should find the "player_start.des" in this folder. Open it with Notepad.

Now, find the line saying: "Ship = 1". This tells the game you start with the Toiler.

You can change the number to: 1 for Toiler, 2 (Drowsy Maggie), 3 (Avenger), 4 (Tiburon), 5 (Shipjack), 6 (Vortex), 7 (Succubus 2), 8 (Voodoo Breath) and 9 for the Phobocaster. After making the change, save the file and start the game.

NOTE: The Voodoo Breath won't take off in the first mission. I recommend taking the Phobocaster.

Have Fun!

Killing enemies easily
When using the "-redrum -stendek" extention, not only can you use the F7 F8 F10 F11 and F12 key, you can also use the F9 key. This is how it works: in the game use the F9 to nuke any targeted object (this can be friendlies or enemies so be careful). And whats more? You can use it against any size of ship, object, building... you name it! (This is pretty useful when wanting to kill that huge beast in the last mission (the one which eats Sam Korhonen's sub) or all the little Crawlers which are hard to shoot).