Turtle's Shell is a powerful magical barrier that can be instantly summoned by a wizard. Within the shell the mage is almost untouchable, but he or she cannot move from the spot where the shell was created.
When a young Cabe Bedlam first met his father Azran, he unconsciously protected himself with a Turtle's Shell. Knowing that Cabe could not move from the spot where he created the shell, and therefore remained a prisoner, Azran did not bother dispelling it.[1]