Well, not really but I still think this goes farther than a coincidence, allow me to explain:
Both creatures were officially named in 2011, for Pokémon B/W and Dragon Quest VI DS remake; then you got the fact that the Dragon Quest series, despite being all the rage in Japan and one of the most veteran RPGs out there, it's still hardly known outside its home country. So, Nintendo eminence Satoru Iwata is currently helping the franchise reach notable levels (only, he's supposedly doing so with the upcoming Dragon Quest X, not VI and that issue should correspond to NoA anyway. Still, the point is, Nintendo is currently helping out Dragon Quest reach some more popularity). So! Knowing Pokémon is really well known outside of Japan, they are trying to somehow relate these two not-so-different franchises
... or it could still just be a very rad coincidence. I just know that thanks to this guy I understand where Haxorus' name comes from. =P
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