I do deer burgers all the time. Just add an egg or two, and some seasoning. I usually add some onion soup mix and/or some Pappys beef rub (that I received in the exchange, BTW), some garlic. Make my patties, throw in smoker with hickory until they hit about 120 or 130 degrees IT, then onto my hot propane grill until they hit 150 to char them up a bit. By smoking first, it retains a lot more moisture. They are never dry, and the best burgers ever. No added beef. If you are worried about dryness, maybe add about 10% beef, no more.