After 9 years this tower defense roguelike is still king, and you have less than 48 hours to get it for free

gamesradar.com:

Dungeon of the Endless is one of the first games I remember writing about, and in the nine years since its release, I've never seen or played another roguelike quite like it. So I was extra delighted to see that developer Amplitude Studios is currently giving it away on Steam.

You have until 10am PT / 1pm ET on Thursday, July 27 to claim a copy of Dungeon of the Endless and keep it forever. Even if wasn't currently free, I'd still recommend it because it's every bit as fun now as it was in 2014. 

Dungeon of the Endless is a fiendish little tower defense game with a unique wrapper: you're defending your energy core from waves of enemies in procedural dungeons, and the more you explore in search of resources, the more paths enemies can follow. You command a crew of heroes who are key to combat along with your installed defenses, and directing them in the middle of a wave can get hectic quickly. 

The genius of Dungeon of the Endless, which is so compelling that Amplitude is currently preparing a successor called Endless Dungeon, is its ability to make classic tower defense gameplay even more replayable and considerably tenser. It's radically unpredictable compared to most tower defense greats, constantly shifting from calm to clamor, so you're always on your toes. 

For example, every chamber you open is an exciting mystery box. It could contain tough enemies or valuable items, and it will always add another room to account for when the next wave comes. You have limited power to spend, and any rooms you leave unpowered will spawn enemies, so you have to balance exploration with your resource bank. Will you let one nearby room stay dark and focus your defenses there, or invest in a long, well-lit path so all the enemies spawn