Magical "Apples"

When Piper first found herself in the Failed Higher Realm she saw a tree in the distance with an apple on it. Except it wasn't really an apple. That was just how her eyes perceived it. It was however the only way to leave.

The All or Nothing
The Angel of Destiny tricked Piper into handing her the apple. Once she had it, she tossed it up and down repeatedly as she told Piper about where they were. Then, when she had finished explaining, she took a bite and both she and the apple vanished. Finally realizing what the apple could do, Piper was about to start searching for another when one was held out to her from a surprising source. Cole Turner had somehow found his way to join her.