I'm probably late (sorry, very busy), but I'll post my top 10 anyway, in no particular order.
Spelunky: The gameplay is flawless, the level generator does an impressive job at creating fun worlds to play through (and die in), the multiplayer is pure mayhem, art & music are great - what is there not to like?
Papers, Please!: It is a mystery to me why this game is so engaging, but it is. The premise is pure genius.
Skullgirls: I'm pretty bad at fighting games, but I really enjoyed this one. The art is spectacular, it's got a cool vibe and a smooth soundtrack. I'm looking forward to the Kickstarter content.
Frogatto & Friends: Fun little platformer that harkens back to the classic era. Had a good time with it, even though I hate frogs.
Gone Home: A lot has been said and written about this. It's a really mature game with a lot of attention to detail, and a very important game that will hopefully inspire developers and storytellers going forward. I'll leave it at that.
Brothers: A Tale of Two Sons: There's a minimalistic quality to this that really jived with me. The way the story is told, the lack of UI, the clean and, at the same time, cartoony look. A really refreshing experience for me. Really interesting and solid puzzles in this one.
Shelter: I'll start out by saying: Pid looked and sounded amazing. The gameplay was terrible. One of the biggest disappointments of this generation for me. There's no doubt that it was made by talented people. Shelter is further proof of that. It reminded me of 'Papers, Please!' with its dense artistic direction and its outlandish premise, especially. Quite an emotional experience.
Guacamelee: A metroidvania with a phenomenal artstyle. And it looks great. Also, it's a metroidvania. That sums it up, I think. (The gameplay is completely serviceable, as well.)
A Good Husband: Very simple and short game.
Here's why I liked it.
Slayin': I play the iOS version from time to time. A fun time waster and definitely one of those ''one more round!'' games.
Honorable mention:
Icarus Proudbottom Teaches Typing: Some good humour in this, got a few chuckles out of me. Basically the only reason this is noteworthy in my eyes.
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Still need to go back and play some games that I just didn't have the time to jump into like Assault Android Cactus, Deios, Postmortem and some other stuff. It's been a good month.