The Gamest of all Mooks

Every time I search for "NEO GEO" on ebay, there's garunteed to be at least 5 items that have the description 'Gamest Mook'.

What's the big idea with it? I just don't understand what it means.

it's an arcade game magazine. neo-geo was a big part of the arcade scene and IS still in the modern arcade game magazines.