The Unicorns and the Witch

Una says, "Let's go into the forest. We've never been there before." Umber says, "I don't think sooo. I hear that a witch lives there." Tyrian, the royal purple unicorn, is lying on the cool grass. He says, "Come on. Let's go! Where's your sense of adventure. We have our magic to protect us." What will happen when they meet the witch?