Full Cheatable Games?

yes, but can you be more specific?

PSX games :D

Hey, if a guy wants to cheat and have fun, I'm fine with that (as long as it's not in multiplayer of course!) Most modern games have done away with it as far as I know. If you go to classics up into the 2000s most games have cheats. After that, you are better off looking for game trainers. They function very similarly, but instead of entering codes into a console you have quick keys that make the game do certain things (invulnerability, all ammo, things like that). Any specific genre you're looking for?

Half-Life 2

Fallout 3 and New Vegas, Saints Row, GTA series

Well I used cheat codes on Serious Sam HD: The First Encounter halfway through cuz it got so boring just killing waves of mobs non-stop. Would be fun if you like going man-mode spartan one-hit killing hundreds of mobs.

All games. With Cheat Engine :-D

Don't try it with online games though. The banhammer will be heavy.

Btw, if you ever wondered about those "999 trillion" scores on some online Flash games, this is how they cheat on those.

Postal 2 , when you finish the game there is bunch of cheats you can use ^_^

And they released a new update , which contain so many stuff XD

And its now 75% , great timing to buy in great price XD , here is the link http://store.steampowered.com/app/223470/

There are too many of those to list. The single player games without known working cheats tend to be obscure games without built-in cheats and that people didn't bother to make cheats for.
I'm surprised that there aren't more working Drakensang (just about none), Hitman series (most outdated, most not working), TBfM-eII+TRotW-k (outdated, missing features), DmC (buggy), C&C RA2 (missing useful features), GTA 4 (buggy), Aquaria (none), Braid (none working), Brütal Legend (none really working), the Cave, Star Wars: The Force Unleashed (outdated, missing useful features), Restaurant Empire 2 (missing features), Homefront (outdated/straight up not working), Fortix, and Just Cause 2 (all are buggy/outdated) cheats.

i loved when every game had console cheats... now it really suck that only a small amount of games are cheatable

Depends on what you mean by cheating.

Some games let you access the console so you can give yourself loads of items / over powered stuff (Fallout series / Elder Scrolls series for example).
Some games can be modded to be 'cheating' - such as Just Cause 2 can be modded so that things are more powerful or free in the black market.
Some games (especially older ones) had actual cheat codes that you typed in - such as Age of Empires.

There's loads. Most single player games could be modded or have consoles that can be accessed for cheating purposes I guess?

skyrim, dmc, anything that has a trainer.

skyrim

help (whatever item name is ex. steel sword)
find item code (ex. 2300cd322)
player.additem ex. 2300cd322 1-whatever amount you want
press again and enjoy

Gothic 1 & 2

Some that I know of:
Quake 1 & 2
Duke Nukem 3d
DOOM 1-2
Hexen1-2 & Heretic
AvP (the first one at least)
Half Life 1 (don't know about 2)
Realms of Arkania 1-3 (there is an editor for this game)
Elder Scrolls series
Fallout series

I've not cheated in a game in a long time, but I guess there are more than those.

Just cause 2

Tony Hawk American Wasteland

Dragon age origin and dragon age 2. I suggest to use cheats since the game has some bugs and make it in some part unplayable if you don't use mods.

Vampire bloodline use cheats
Starcraft 1 and 2, both expansion

Warcraft 3
Mass effect 1 you can use codes
That all that i can remember, you can find them on google there are list or on the wiki off the game, just write console and will give you the information you need

On PC almost any single player game, really

The Sims

I remember Enter the Matrix and Tony Hawk's American Wasteland having some good cheats.

Minecraft you can cheat whatever you like, depending on what you like to do it will be funny.

-Up, Up, Down, Down, Left, Right, Left, Right, A, B.
-showmethemoney
-blacksheepwall
-operationcwal
-thereisnocowlevel

There's trainers for almost every single game in existence

All the lego games if u can find the cheat codes for them