I cant get into the dark world on the legend of zelda a link to the past?

well, do you have the moon pearl? you have to have have completed all 3 dungeons with the pendants. you have to get all the pendants, then you will go and obtain the master sword and then something terrible happens, you have to go back to the castle that you went to in the beginning, and fight a boss who you have to attack his attacks which are magic balls that come at you and deflect them back at him. you will be thrust into the dark world cuz he's a sore loser. -3-