When it comes to a serious mass gain - the Mutant brand has been famous for their Mutant Mass Gainer. When it becomes one of the best selling weight gainers in the World Mutant decided to develop their other products. So here came Mutant Whey, ZMA, creatine Creakong, pre-workouts like Mayhem and Madness been selling off the shelves immediately! But their best ever product was the Rehab - after workout All-in-one recovery drink. It's a shame that it is discontinued now.