The Humble Store is one year old today, and to celebrate there will be a number of sales on certain PC games, but the better news is that the excellent Metro 2033 will be free to anyone who shows up for the first 24 hours of the sale. You just need to log in and redeem your free copy of the game.

Here are the other deals:

75% off Sonic Hits Collection



50% off Banished



75% off Batman: Arkham Origins



80% off Crusader Kings II Collection



and much more!

Those are good deals, but a free copy of Metro 2033 is the real draw. This isn't the Redux version of the game, but the original still provides a sense of desolation and despair that's rare in modern games, even if the shooting itself can feel a bit flat. There's a reason it's so well regarded despite its flaws, and this is a great chance to see for yourself.