Every year, NeoGAF has a 52 games challenge, in which you have to beat 52 new games before the start of the next year. There is also a movie and book equivalent, in which you have to read 50 new books and watch 50 new movies. These challenges provide that extra motivation to do/finish the things you already wanted to anyway and can lead you to checking out stuff you otherwise may not have (this is especially true with books).
I didn't even come close to completing the challenge, beating only 18 games during the entirety of 2015.
My ratings are done on a 5-star scale (no halfsies). I didn't rate all the games I beat for 2015.
★ - Hated it
★★ - Disliked it
★★★ - Liked/enjoyed/didn't actively dislike it
★★★★ - Really liked it
★★★★★ - Loved it
For games, I sometimes wrote a sentence or two about my thoughts and experiences, which are included here. I also include about how many hours it took me to complete some games.
Here are the 18 games I beat in 2015:
Game 1: Knack - ~10 hours - ★★★
Longer and more challenging than I expected, Knack was an enjoyable action-platformer that felt very much like something from the creator of Crash Bandicoot.
Game 2: Depression Quest - ~3 hours - ★★★★★
A very accurate portrayal of depression that hit a bit closer than I expected, Depression Quest is an important experience that those who wish to know more about the illness should play.
Game 3: Tom Clancy's Splinter Cell: Blacklist - ~21 hours - ★★★★★
Much better and truer to Splinter Cell than what I was initially led to believe, Blacklist is a great addition to the franchise that allows a lot customization and freedom in how to handle situations. The co-op, as always, was the best part of the experience for me. I completed all the 4E missions including the DLC with random partners.
Game 4: Final Fantasy XV: Episode Duscae - ~5 hours - ★★★★★
Game 5: Borderlands 2 - ~83 hours - ★★★★
I played the entirety of this game and all of its story DLC on co-op with my friend Sean. We begun on August 23rd, 2014 and just finished up everything on March 27th, 2015. An overall enjoyable game that can get tedious at times, we ended up ignoring most of the enemies near the end as we were so over-leveled by that point it didn't matter. Tiny Tina is the best.
Game 6: Ryse: Son of Rome - ~10 hours - ★★★★
Game 7: Mortal Kombat X (iOS) - ★★★
Game 8: Batman: Arkham Knight (PC) - ★★★★★
A fantastic game all around, and probably the most technically impressive I have played to date (July 25th, 2015). Really liked the story, and the writing for one character in particular was top notch. Game of the Year contender for sure. Oh, and I liked the Batmobile!
Game 9: Metal Gear Solid 3: Snake Eater HD (PS3) - ★★★★★
Game 10: Metal Gear Solid: Peace Walker HD (PS3) - ★★★★★
Game 11: Metal Gear Solid V: Ground Zeroes (PC) - ★★★★★
Game 12: Metal Gear Solid V: The Phantom Pain (PC)
Game 13: Metal Gear HD (PS3) - ★★★
Game 14: Resident Evil 5 (PC) - ★★★★★
Game 15: Until Dawn (PS4)
Game 16: Star Wars Battlefront (PS4)
Game 17: Adventure Time: Magic Man's Head Games (Gear VR)
Game 18: Nidhogg (PC)