Undertale aka one of the best purchases of my life, although, I never expected NOT to enjoy it, I just came in with no expectations at all, and that's pretty much how I would want to approach every game in the future now, I mean, it won't happen, but it would be cool.

Monster Hunter 4 Ultimate - Never played the MH franchise before, it just seemed boring to me. Too much farming. Too repetitive. And I have spent over 300+ hours playing it. Its just awesome.

ETS2, you drive a truck, it's slow, why is that fun, for 124 hours no less.
Terraria, surely the stats are wrong, 441 hours? (some of that is from my kids, phew)
DDR, long winters, staying fit, yet beating 8 ps2 versions was a bit overkill.
Minecraft, once I started messing with red stone I couldn't stop.
Dark Souls, bought it second hand to confirm it sucked.
Just Dance, April tournament is mine. It's got down to compensating for display lag.
Tired of killing things I guess, and it makes my wife laugh. 5 stars, nailed it! not.

I Bad mouthed hyrule warriors so much when it was revealed. Then, logged in so many hours after it released.

Fire Emblem awakening, wasn't expecting much but I got hooked inmediattly (and after I found out about the children I played the game again because I let some of the females that have kids die)

Gravity Rush took me by surprise so hard when I picked it up.

I remember renting Worms: Armageddon on N64 with a buddy back in the day just because our local video store didn't have much else in the way of new(er) games at the time, thinking we'd play it for a couple hours and get bored. We ended up renting it several times more (complete with late fees) before I finally tracked down a copy at retail and bought it, eventually spending countless hours of multiplayer with my buddies.

Smash on N64 was another one of those games that looked "meh" at first, and it barely received any hype prior to release. Once I played it at a friend's house though, that instantly dethroned GoldenEye as the #1 multiplayer game at the time.

This past gen I also downloaded some XBL Arcade games that were free with gold just for the hell of it, and ended up loving some of them like Dust: An Elysian Tale.

Mass Effect

I use to hate RPG's. Too confusing, and generally just a loss of direction. Mass Effect felt very different though. Certainly one of my favourite franchises of all time.

DarkSiders and Dishonored!!

FIFA for sure. It's been such a guilty pleasure for me. I just really enjoy playing manager mode.

I can also think of Nier and Persona 3 as games I didn't think I would enjoy at all, but I ended up really adoring.