You press ~, it should open the debug editor from there you can enter what ever cheat you want (has to be in all caps). Though some cheats work for certain races if i remember correctly. There really isn't any good cheats for the game besides the god mode and some weapon cheats for marine but here that the god mode cheats.
alien THEONEDEADLYCREAUTUREEVERCREATED
marine FREAKOFTHEUNIVERS
predator SKULLCOLLECTOR
I will be able to help you more once I actually get the key, they seem to want to do separate test runs at a time so i don't blame them but >< I really wanna play the game again.

The way it worked for the original release of the game and the Steam version is that you had to type in -debug at the end of the command line (Properties -> Target). However, I just tried this with GOG and even after having changed the target, it doesn't start in debug mode and the cheats don't work.

Also, FYI, when typing the cheats you need to press tilde (~) and delete SAY, type the cheat in all caps, press enter, then type SAY again and hit enter to get out of the console.

I found the solution, it's the launcher that's blocking cheats (a good idea i guess)

So go to "C:\GOG Games\AvP Classic" and create a shortcut for "Launch Aliens vs Predator Classic 2000"

Then right click that shortcut and in there enter -debug (i.e. "C:\GOG Games\AvP Classic\AvP_Classic.exe" -debug)

Then start your game, press T then press backspace to remove the "SAY" then just enter in any of these codes

http://www.ign.com/cheats/games/aliens-vs-predator-1999-pc-3952

If something doesn't work let me know

Now go and wreck havoc on the galaxy ;)

FAIR WARNING:

You CANNOT save the game while using the dubug mode

Also when in normal game play (no debug) try -unlimitedsave for infinite saves, not sure if this works, never tried it

ok... i've been trying to get the cheat console working (press T and remove "SAY") for two days now and just now it came to me to try and execute the game in compatibility mode for windows xp service pack 3 with the command line parameter "-debug" and IT FINALY WORKED!!!!!!!!!!!!!!!!!!

Is there any cheat to acess last bonus levels (for which you have to finish the game on director's cut difficulty) ?

No, but you can download a complete profile for that purpose here: http://www.moddb.com/mods/aliens-versus-predator-classic-redux/downloads/complete-profile

Thanks!

none of it works..i added debug

did it in compatability mode

i go to enter code and delete say....and enter code...nothing happens..ill never get cheat codes working

The cheats work, you are just doing something wrong.




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Issue I'm having is with the cheats enabled I can't advance to the next mission. I can complete the mission I'm on but instead of loading the next mission it goes to the menu.

Hello! Its working, but how hide console after entering any code?

To be honest, its been awhile since I played this game, but in most games you can hide the console by pressing the button you used to bring it up, so in this case it's T. If that doesn't work, try pressing Enter when there is noting typed in the console, and if that doesn't work, try pressing Esc. Let me know what works!

Thank you for answer! Works another variant, which I find in some site. After entering code (example, "GOD"), then remove it and enter "SAY" again.

My problem is that for some reason the bastards disabled saving when using cheats! But I need to sometimes cheat to get through a REALLY tough part, otherwise I just can't possibly do it! But then I can't save so I can't finish the game anyway!!! So my question is how can I enable/disable cheating during the game so that I can enable it when I need to use it and then disable it so that I can save again?

No problem. I have two alternate workaround solutions for you. One is to enable unlimited savegames, you can read it here on how to do that:

https://steamcommunity.com/sharedfiles/filedetails/?id=421084750 Scroll down to see the instructions for GOG.com version.

Basically the way to enable it is the following steps:

1. Open up your AvP Classic folder. The directory should be: Your Drive:\GOG Games\AvP Classic
2. Right-click the Launch Aliens vs Predator Classic 2000 shortcut.
3. Go to Properties.
4. At the end of the target line, type " -unlimitedsaves" (without the quotes). Make sure there's a space between the last quotation mark and -unlimitedsaves.
5. Hit Apply, then OK.

Or you can download and use pre-unlocked game profile that gives you access to all of the single player levels/maps, contents. You can get them here:

https://www.moddb.com/mods/aliens-versus-predator-classic-redux/downloads/complete-profile

https://www.moddb.com/mods/avp-classic-improvement-project/downloads/avp-gold-edition-completed-profile

Despite it says "Gold Edition" the original files for a profile is 100% fully compatible and interchangeable between the Gold Edition version release of the game and the current more recent release version of the game: Classic 2000

Basically, you want to extract the prf file into the appropriate directory.

By default it would be something like this: C:\Users\User\Documents\My Games\Aliens versus Predator\User_Profiles

The User may be different because the username you have on your computer might be different, so for example if your username on your computer was "HereMyAccount" then the appropriate directory to extract the prf file would be C:\Users\HereMyAccount\Documents\My Games\Aliens versus Predator\User_Profiles

Enjoy! Let me know if you encounter any really difficult problems. Basically when everything is fully accessible you can now cheat away without being penalized by not allowing you to further advance into the game's later levels.

However, if you want to create a savegame or save the game while you are using "God Mode" there does not seem to be a work around for this. But it can sure help you significantly develop you skills at the game first and then start a new profile from scratch and beat it without cheats, because that's what I had done back in the day, particularly for the Marine as it was a pain, especially in the later levels.