Yes, human urine!
All urine has a very high nitrogen content and it's basically the urea that is leaving the odor behind. Provided you aren't eating a ton of odd food, ie garlic, peppers.., deer will not even flinch at the smell you leave behind. I have even experimented with straight ammonia. Wasn't sold on the results though, plus my urine packs easier. LOL
I just gathered up more trail cam photos for the week. I created a mock scrape under a pine tree bow last Sunday (I know, not the desired licking branch). The 2.5 year old buck that visited it the same evening must not have cared too much as he investigated the scrape and the licking branch while posing for the camera.
Give it a try. Trail cam pics don't lie.
Hunting the Michigan Thumbs agricultural mecca...farm country bucks taste the best.