This is the wallpaper background for the game called Castle Clash which you can download and use as your Windows desktop PC wallpaper on your monitor by right clicking it, and then choosing to set it as your desktop wallpaper background. If there is no option for that then you can right-click and save the file image to your computer, and then locate the file on your computer and then right-click that file and set it as your desktop background.
Castle Clash is a strategy game that was developed by IGG and has since become a hugely popular game on the Google play store. It has an incredibly high rating of 4.6 stars from nearly 3,000,000 users from around the world. That includes close to 2.5 million five-star ratings compared to less than 200,000 one star ratings.