This may come as a surprise to some, but not all pain relievers are the same. In fact, the difference between many over-the-counter pain relievers can have various effects on your body. People sometimes refer to a specific over-the-counter medication (OTC)--Tylenol, Aspirin, Advil, etc.--even if they donât have a specific brand in mind. The U.S. Food and Drug Administration (FDA) considers all three effective for the same minor aches and pains.
Fairy Type Pokemon are countered by Poison Type. For Example, Muk (Poison type) will deal increased damage to Clefable when using any Poison Moves against him in Gym Battles. However, it will also take decreased damage when attacked by Fighting, Dragon and Dark moves.
As stated up there in my comment, Heatran is an ideal counter to Clefable. Standard Clefable sets have nothing to hit it. All you really need to do is keep it relatively healthy and you can stop Clefable easily. I suggest Heatran over other Steel types, and there is two reasons for this. The first is its Fire immunity, as most good Clefable sets run Flamethrower.