If you get this error that says missing D3DX9_29.DLL , do the following steps

1. VIsit https://www.dll-files.com/
2. Search for the correct version (32 or 64 bit) of the file D3DX9_29.DLL and download the .zip file.
3. Extract the file
4. Place the d3dx9_29.dll file in the Games folder under the "C4" folder. It should be somewhere under Program Files.
Example: C:\Program Files (x86)\Steam\steamapps\common\Caesar 4\C4\d3dx9_29.dll
5. Launch the game

If you get 0xc000007b error, then you haven't downloaded the correct version. Check if your ProgramFiles folder where the game folder is located is named ProgramFiles (x86) --> x86 would mean that you're running 32 bit.