God of War has a beautiful world and graphics to match, so it only makes sense to want to play it in an Ultrawide resolution. God of War supports 21:9 but some players are experiencing issues in running the game in Ultrawide Aspect Ratio.
Even though the Steam page shows that God of War natively supports the 21:9 aspect ratio, players encounter launching issues when setting their resolution to ultrawide. To fix this, you will first want to download the Flawless Widescreen application.
Select the version of your Windows and wait for the download to finish. Make sure you launch the Flawless application first before launching God of War. Choose the God of War plugin and you should be able to play in full screen.
If you are experiencing issues with launching the game in full screen, you may want to check your graphics drivers if they are up-to-date. You should also tick the “Fix Enabled” option, as well as all the updates in the application.
Launch the game and you should be able to play in full screen without any borders!