Huh ... I'm kinda surprised to see some people mentioning Kirby Triple Deluxe. Great showcase for the 3DS but it's obvious to me the better release came in 2016 ...
Anywoo, In hindsight, it'd be quite easy to choose MK8 due to the evolution it went through during the years. But I'd say, once the DLC tracks were there. The racing portion of the game became complete and legendary imo. Totally my GOTY there.
Also DKC Tropical Freeze silently defined this generation of platformers but the initial reception was mute due to the "Retro not working on a Metroid game instead" debacle. Knowadays seen as one of the best platformers.
Alien Isolation is also a pretty good candidate to how revolutionary the AI used there was implemented for the aliens. 1st half of the game is without a doubt one of the most scary experience you could've had at the time.
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