https://www.gamespot.com/articles/you-can-get-another-free-game-on-steam-but-hurry/1100-6458868/

Anyone on the hunt for free games has a couple of worthwhile options today. First, Oddworld: Abe's Oddysee's price got dropped to zero on Steam for a limited time. Now Yet Another Zombie Defense has done the same. You can download it here for free. But hurry up, because the price goes back up on Friday, May 11.

While it's not the most visually stunning game on Steam, don't let the self-deprecating title fool you: there's fun to be had here. The setting is a gray span of ground centered around a light post during the zombie apocalypse. During the day, your job is to build up defenses like weapon turrets and spiked barricades to create a secure base. When night comes, so do the zombies. The goal then is to stay alive as long as possible. Ideally, the sun will rise on a landscape spattered with the blood of zombies, and you'll be around to start again.