here is something my father-inlaw uses when he cooks wild meat.
He cooks roasts & steaks with this recipe. It really tenderized the meat and removes alot if not all the wild taste

1 pouch dry onion soup mix
2 cups of black coffee

mix together pour over meat and cook in oven on about 250 until done, the amount above usually does a good size roast. just divide for smaller pieces.