Years later, a teenage Merlin recounts to Ambrosia how he has rescued a nobleman's daughter, Nimue, from drowning by magically growing a small branch. Ambrosia tells him of his past and he is sent to Mab to begin his training with Frik, Mab's gnome servant; however, Merlin has little interest in helping Mab's crusade to restore the Old Ways, angering her. Merlin finds out from the Lady of the Lake that her sister Mab let his birth mother die and that Ambrosia is ill. Mab reaches Ambrosia's home before Merlin, but when Ambrosia refuses to convince Merlin to return to Mab, Mab lashes out fatally injuring Ambrosia. Merlin tries to attack Mab but can't defeat her; she dismisses the deaths of his mother and Ambrosia as "casualties of war" and vows that Merlin will help her in her quest for power. Merlin makes a blood-oath never to use magic.