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Pretty strong year IMO.
The obvious heavy hitter was The Witcher 3. Really good game, but in going open world it lost the attention to detail of TW2, which is, IMO, the better format for telling Witcher stories (and thus I prefer TW2). In addition, being touted by devs as influenced by Gothic, it didn't have as much of the freedoms that Gothics have, so was a slight disappointment in that regard for me as well.
Bloodborne was something I tried, and didn't like that much. I do need to give it a second chance eventually, but I don't care for that setting (as opposed to Souls) and not having shield is also not to my taste.
Fallout 4 was mostly disappointment - Fallout 3 was already Fallout reduced, with NV being glimmer of hope, but FO4 was, although with improved action mechanics, a further step away from original Fallout design.
I don't play a lot of online stuff (apart from some niche things), but both Rocket League and Splatoon were massive hits and are easily contenders for GotY.
Soma was a pleasant surprise for me. I must admit, I didn't care much for Amnesia, although I really love their first game, Penumbra, so was both a bit reluctant and curious about this one. Liked it quite a bit. I guess it's all about setting for me when it comes to horror genre, and this one being placed in an underwater research facility hit the spot.
On the opposite side of what's fun, there was Just Cause 3. I liked the first two so-so, but this one was just pure silly fun with all the destructible physics and parasailing/paragliding.
Kerbal Space Program officially launched that year, but that one I consider as a 2013 release, given the amount of community content it already had prior to offcial release.
Ori and the Blind Forest was a superb 2D Metroidvania with fantastic art style. One of my favourites from that year.
Dying Light came as a complete surprise to me - I remember after watching the first reveal trailer not being very interested in it (although I am a sucker for a good zombie apocalypse and liked both Dead Island and Mirror's Edge), yet when it launched, after watching some gameplay, I decided to give it a go. Oh dear, was I wrong - I really liked that combination of parkour, melee fighting and overall atmosphere of the game. It overstayed it's welcome a bit in the later part of the game, but I still remember it as one of my favourites from that year.
I'm not a big fan of SMB type of platformers, but I got Super Mario Maker for my kid who is a fan, and I spent quite a bit with it fooling around and making levels for him to beat. It reminded me of some of the old games from C64, like Kickstart which was a motorcycle obstacle course game, which had level builder - a lot of time spent in that on when I was a kid.
Another great WiiU game was a great puzzle/exploration adventure called Affordable Space Adventures. I played it coop with kids, all playing different crewmembers with our own tasks and having to coordinate and time things properly to succeed in overcoming obstacles.
A mobile game that surprised me a lot was Lara Croft Go. As a TR fan who got very disappointed with what was happening with the IP since the Reboot, smaller TR games were my last hope that the spirit of old TR is still alive, with this one (in addition to "Lara Croft and the..." series) being quite enjoyable.
CRPGs had quite a year with Pillars of Eternity, Underrail and The Age of Decadence. Pillars was the second large Kickstarter (after Double Fine's adventure) that have shown that there is a market for old school games, and one with the biggest budget out of those three. AoD is probably the most rough around the edges, yet most distinct one in actually being most similar to tabletop RPGs in its options of how to play and where combat is something you actually really don't want to do unless you absolutely have to.
Indie games had a fantastic year as well: Undertale, Crypt of the NecroDancer, Besiege, Sunless Sea, Invisible, Inc.. Two especially stood out for me, Lovers in a Dangerous Spacetime, which was another game that you could play coop, controlling different stations throughout the spaceship you're on, and my favourite game from that year, Westerado: Double Barrelled, open world top-down pixel art shooter set in the Wild West, with a lot of that Spaghetti Western feel to it, which can also be played in coop. Fairly short, but very sweet.
Ultimately, although not my favourite, I have to give my vote to The Witcher 3. It was less that what I wanted and hoped for (both when it comes to as Witcher game and "Gothic influenced" game), but it was and still is a pretty good package overall.
