Many bodybuilders and athletes have switched to prohormones to gain an incredible amount of muscle mass and strength. Prohormones have proven to create Muscle Mass and strength gains at a much more rapid pace than if you were to lift without them. This substance converts to an anabolic hormone increasing your ability to gain a large amount of muscle mass in a short period of time, as well as strength. This has become very popular nowadays due to the amazing results that users have reported.
Due to the legalities of M-Drol, Superdrol and others, clones have been made to replicate if not improve the results that these prohormones may have originally had. Take a look into Mechabol and Trenavar.