I'd say pronghorn antelope... I could never seem to get within 2 miles of those things growing up and if you stepped on a twig by accident you could just see the herd move off like a big black blob on the horizon...
Elk are a pain and probably some of the most elusive game I've ever had to work with, they cover vast distances in short periods of time and they have amazing hearing and smell...
turkeys also are difficult but so far that's the only animal I've ever managed to actually call in so I don't think they get the nod, at least in my eyes.
ignore my complete lack of capitalization. I still have no problem correcting your grammar.
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