Tiger King pills work because the herbal extracts were clinically tested. One of the most powerful ingredients is called velvet deer antler. Several studies were carried out to examine the efficiency of velvet antler for the treatment of male sexual problems. In one experiment, a group of 32 men received the supplement for 12 weeks and a second group was given placebo. The men who took the actual extract experienced significant changes in the level of testosterone, which resulted in better sexual performance.