Ultra-X-Amine is a chemical or drug that can cause a sudden emergence of mutant powers. It was discovered by Dr. Cory Fielding in the late 19th century. Most people experience few effects, but it causes the sudden emergence of wild powers in a few. Most of these die. The few who did not die became the Mystic Six. The formula was supposedly lost. Apparently a supply was rediscovered, and then used on Bill Wilson, turning him into Tennyo.