The muscle and strength gains with Dianabol is so exceptional that it will always be a favourite among athletes even with the side effects of water retention and strain on the liver and kidneys. If you add a mild anabolic steroid like Deca to Dianabol the side effects are not more than when you take Dianabol on its own but the results are better. For sheer mass many athletes add a Testosterone Cypionate or Enanthate to the Deca and Dianabol stack. Dianabol can not be used pre-contest. Even with a anti-estrogen the muscles will look very bloated and you will most likely loose definition on this super bulking agent.
The most commonly used AAS in medicine are testosterone and its various esters (but most commonly testosterone undecanoate , testosterone enanthate , testosterone cypionate , and testosterone propionate ),  nandrolone esters (most commonly nandrolone decanoate and nandrolone phenylpropionate ), stanozolol , and metandienone (methandrostenolone).  Others also available and used commonly but to a lesser extent include methyltestosterone , oxandrolone , mesterolone , and oxymetholone , as well as drostanolone propionate , metenolone (methylandrostenolone), and fluoxymesterone .  Dihydrotestosterone (DHT; androstanolone, stanolone) and its esters are also notable, although they are not widely used in medicine.  Boldenone undecylenate and trenbolone acetate are used in veterinary medicine .