We are Mutant – Leave Humanity Behind. Mutant Mass was the first to arm the Nation of Mutants with the world’s #1 weight gaining formula. Since 2006, MUTANT MASS has become the gainer of choice among bodybuilders and powerlifters in over 85 countries worldwide. After years of experimentation, the Mutant R&D lab has developed new and powerful bodybuilding supplements. Their plan was simple – to modify your regular workout into absolute iron-crushing chaos that forces your muscle and strength into the freak zone! No “curls for the girls” or “coreball crunches” in the Mutant lab – nope, Mutant is for those who want massive size and strength, period.