Xenoblade Chronicles 3D is the first game that actually required a New 3DS.
I was massively unimpressed by this game, and for a while I was unsure as to why. It had a potentially interesting setting, an open-ish world, a veritable boatload of sidequests, events tied to the day/night cycle, and a non-standard battle system. Then I realized that I was effectively playing a single-player MMO with hotbar combat and ‘get me 10 bear asses’ quests. The fact that it didn’t even compare with 2005-era WOW was just the icing on the cake. The story wasn’t doing it for me, and the characters were grating, so I stopped.