When I decide to hunt the ground I just build my own out of small pine trees, camo burlap and some string and put a chair in the middle, has always worked well and kept me out of detection.

Once when I was 15 I had alot of time on my hands and I built a blind underneath the ground with a little staricase and hole to crawl through, also had one of those windows like the bunkers in WWII. Needless to say I could make every mistake possible in that thing and I got away with alot of noise as well. It was really quite neat! I was proud!