PlayerUnknown's Battlegrounds first trialled flare guns in March, within a titular event mode set on Miramar. They've reappeared in other limited-time forays since, and now PUBG Corp is considering installing them full-time. Live now, Flare Gun Stage 2 acts as a public beta.
"This week’s event mode is going to be another test of the Flare Gun system," explains the developer in this Steam Community post. "We’ve looked at your feedback from the last round, but want to gather a little more data before we pull the trigger on any changes or deploy the item to live. Unlike the long event before, this test will run from Wednesday until Saturday."
Live now through October 13 at 7pm PDT / October 14 at 3am BST, PUBG Corp talks feedback, application and the future of flare guns in the main campaign: