To celebrate the arrival of darkness presumably Microsoft has released a new set of free Windows 10 themes to the Microsoft Store.
Titled Antlers and Horns, the description of the high-quality wallpaper selection reads as follows:
Did you know male deer, moose, and elk have antlers that shed every year, but goats, antelope, and gazelles keep their horns forever, both males and females? Take a closer look in this 14-image set, free for Windows 10 Themes.
After downloading the collection, go to Start > Settings > Personalization > Themes and click on the theme you prefer.
To apply and change to the most appropriate colour, based on the current wallpaper, go to Customize > Colors > Automatically select a primary colour from the background.
Find the collection in the Microsoft Store here.