In what appears to be an ever growing trend of unlikely games to get a battle royale mode, Civilization VI comes in with Red Death.
Originally brought in as an in-office April Fools joke, Red Death sees up to twelve players compete in a free-for-all battle to escape a planet covered in a storm of radioactivity. Bradley Olson scripted the basic gameplay and added it to an April 1 build only for no-one to notice it. It was only later when he brought it up in a meeting that everyone realised that they had a good idea going there and decided to flesh it out.
The mode is available now and is free to anyone who owns the base game