DARTH VADER THEMED BATSUIT MOD:

(Make sure that your game is running on dx9, to do so head over to Documents\WB Games\Batman Arkham City GOTY\BmGame\Config\BmEngine.ini
open the file with Notepad or Notepad++ and once you are in, click ctrl+F and type "AllowD3D11"
once you done that you should see 2 settings, one says "AllowD3D11" and one that says "AllowD3D10", make sure that both ao them are set to false.
After you done that, hit save and exit the file, then go to the file's properties and set it to read only mode. Congratz! now you can play batman arkham city in dx9 mode)


Now for the actual installation steps:

1) Extract the contents of "Mod Files" into game directory.
2) Open TexMod.
3) Choose the game batman arkham city, this can be done by clicking on the folder icon in texmod and choosing the game exe file, the game exe file adress should be something along the lines of this:
Steam\steamapps\common\Batman Arkham City GOTY\Binaries\Win32\BatmanAC.exe
4) Once you chose the game, on the left side of the program will now appear a smaller folder icon, click on it and choose the file "Darth Vader themed batsuit.tpf"
5) Click "Run" to open the game.
6) View Default Batman in the riddler challenge character section and press the Home key.
7) Enter the game as the 1970's batman outfit and mash the Home key as it loads.
 
Done!

for riddler challenges you need to do step 6 and choose the 1970's batman there, when you choose a mission while it loads, mash the home button as challenge loads.
usually it will not work the first time so if it doesn't, restart the mission and while the mission loads again spam the home button again and it should work. you need to mash the home button everytime you start a new challenge in order for the mod to work.

Credit for the free roam mod is going for mr jag, caplag, wastelander and tchi6

enjoy ;)