Creatine, Beta Alanine, citrulline, and anti-oxidants. IMO you should always take creatine on a cycle, natural or otherwise, in order to maximize gains. Creatine increases the weight you can lift/reps, while the NHA optimizes hormones toward the anabolic side. The lactic acid/carnosine boosting effects of the beta alanine and citrulline are just added bonuses.