Basically all we are going to do is adding a new keybinds into the game that will control the game speed. To do this, we will need to open game folder and edit configuration file that is responsible for key inputs.

I recommend using Notepad++ for editing the configuration file as you can easily see the code groups, but you can still use basic notepad.

1. Open Steam and click LIBRARY
   
2. Find your XCOM: Enemy unkown and right click on it. Select Manage -> Browse local files
   
   
   
   
3. Open the folder called XComGame
   
   
   
   
4. then the folder Config
   
   
   
   
5. The config file you are looking for is DefaultInput.ini. Find it and open with Notepad++ (or basic Notepad)
   
   
   
   
6. Look for code section [Engine.PlayerInput] and then scroll down to its end (right before a new section called [XComGame.XComTacticalInput] starts).
   
   You can use CTRL+F for search and put [Engine.PlayerInput] for easy search:
   
   
   And then scroll down all the way through this section right before a new section starts:
   
   
   
7. Add these new lines right before the green line:
   
   
   .Bindings=(Name="F5", Command="slomo 1.0", Alt=False) .Bindings=(Name="F6", Command="slomo 2.0", Alt=False) .Bindings=(Name="F7", Command="slomo 4.0", Alt=False)
   
   
   
   
8. Now do the same step, but in the end of the [XComGame.XComTacticalInput] section.
   
   Scroll down to the end of [XComGame.XComTacticalInput] section and right before [GFxUI.KeyMap] starts, paste these commands again.
   
   
   
   

Now we have three new buttons that we can use to accelerate in game speed, they work both in combat mode (where you play as marines) and in hub mode (where you build your base and watch the globe).

By pressing F5, the game will run at normal speed.

By pressing F6, the game speed will accelerate x2. Very handy to skip enemy turns and you can still see every enemy movements and vital information on the battlefield.

By pressing F7, the game will run at x4 speed. Its super-fast and useful if you are already a pro and play this game for speedrunning.

If you don't like these button you can use any else you want, like numbers 1 2 3, but keep in mind that they can conflict with in game default settings so you have to rebind them ingame.