In all seriousness, get 2x2' examples of as many different panel and wood products as you can: CDX plywood, OSB, advantech, wafer board, flake board, particle board, masonite, transite, glued up panels of 3/4" Oak, maple, pine, etc. ad infinitum, mount them securely in a sturdy frame, and test them all to see which one you can punch through while starting with your fist 1" away from the wood.
Select the appropriate difficulty of punch through level (were you offed with buck shot, rock salt, bird shot, deer slug?) for your intended scenario and proceed with your build.