I'm using this IFTTT recipe to occasionally get free Steam keys for Indie games. It's a bit of a hassle the first few times because you will need to subscribe to a bunch of newsletters1) and like some stuff on Facebook, but then it works just fine.
Most of the games are mediocre at best, but from time to time some real gems are among them. In the last week I played two that I particularly liked:
Vertical Drop Heros
Vertical Drop Heroes is a procedural platformer RPG hybrid with roguelike elements, where your hero adventures through randomly generated stages. Armed with a variety of skills and traits, you must use your cunning and reflexes to survive the dangers of each stage, until you face the final boss and uncover the truth behind the game!
This game plays great with an XBox controller and is super casual. You pick a hero and play til you die or if you're good enough to make it through the game. A typical round is maybe 20 minutes. Beating the game could probably be done in an hour.
I haven't beaten the game yet (but I came close once or twice). But every play upgrades the abilities of future heroes, so despite the perma-death of your actual here you have some kind of leveling-up going on.
Available on Steam
Life under the rule of the winged Skyborn race isn't so bad for Claret Spencer, the star mechanic of an independent repair shop. She can patch up just about anything… but when a certain cravat-wearing customer turns her life upside-down, she finds herself pulled into an epic, city-wide conflict that's going to take a lot more than elbow grease to fix! Join Claret on her journey through a tale of magic, metal and mystery as she unravels the secrets of the Skyborn!
Playing through Skyborn took me about 20 hours. The game is made with the RPGMaker Engine. It's done in lovely pixel art, but with a tiny resolution. I wouldn't recommend to run it in fullscreen but use the windowed mode. Once you get over having to play in a small window, the wonderful story will capture you. Fights get challenging but never unfair and the characters are well written.
Available on Steam