That's worth noting because I barely played Yuji Horii's first foray into the world of console RPGs. (I was much more captivated at the time by its contemporary, Hironobu Sakaguchi's Final Fantasy.)
"Barely played" isn't a phrase I'd use to describe my experience with Horii's ninth Dragon Quest title. Instead, I'd probably say that I played it so much that I was worried my husband would kick me to the curb. (OK, so I'm exaggerating a bit. You get the idea, though, right?)
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The highlight of such a list, however, would be the title's randomly generated treasure maps--which were pretty much solely responsible for pushing me past the 100-hour mark (and for putting my marriage in danger).
Honestly, I'd probably consider Dragon Quest IX my favorite DS game of 2010 even if it had consisted of nothing more than the above-mentioned maps. That is how much I've played and enjoyed that portion of this title.
That's not meant to suggest there was a dearth of worthwhile releases for Nintendo's dual-screened system in 2010. On the contrary, there were oodles--Etrian Odyssey III, Final Fantasy: The 4 Heroes of Light, Professor Layton and the Unwound Future and Shin Megami Tensei: Strange Journey among them.
As great as each of the above were (and are), though, none of them topped Dragon Quest IX in my mind--which is why I consider Square Enix's latest RPG extravaganza to be my favorite DS game of 2010.
See also: 'Rhythm Heaven: My favorite DS game of 2009'