How to unlock FPS in Batman: Arkham City and make the game smoother

(First, you need to log into the game at least once)

1). Navigate to the settings folder at the following path:
C:\Users\*YOUR USERNAME*\Documents\WB Games\Batman Arkham City GOTY\BmGame\Config

2). Look for a file named BmEngine.ini

3). Open it using Notepad

4). Find the category [Engine.GameEngine]
(To search for text in Notepad, press Ctrl+F (or go to Edit > Find)

5). Change the parameters within it to match the ones below:

• bSmoothFrameRate=TRUE
  
• MinSmoothedFrameRate=0
  
• MaxSmoothedFrameRate=280

~For MaxSmoothedFrameRate=280, ideally, replace the number with your monitor's refresh rate (in Hz); here, my 280 Hz is used as an example.~

6). Don't forget to save the changes for them to take effect

7). Open the properties of this file and check the "Read-only" box to prevent the game from automatically altering the settings we've configured

For anyone planning to play the full Batman trilogy, these guides may be useful
https://steamcommunity.com/sharedfiles/filedetails/?id=3582729584
https://steamcommunity.com/sharedfiles/filedetails/?id=3581556923

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