https://www.pcgamer.com/the-steam-spring-sale-is-live/

The Steam Spring Sale—that is, the Steam Spring Cleaning Event—is now live, with Daily Tasks and Projects to complete, trophies and a profile badge to earn, and some pretty good deals on games, too.

This one looks a little more complicated than the previous activity-filled Steam sales we've seen. Instead of just blindly blasting through your Discovery Queue, you'll need to actually play some of those never-before-touched games in your backlog, including some chosen for you by Valve. To help make that happen, a number of games are being made free for the weekend, including Borderlands 2, Middle-earth: Shadow of Mordor, Cities: Skylines, Tyranny, and Castle Crashers.