The Heart of the Serpent was an Atlantean substance that permanently bonds to whoever ingests it and makes them resistant to magic. If ingested by a magic user, it severs their ties to magic and makes them unable to practise it anymore. The Heart of the Serpent was liquid in its original and purest form, but it had been solidified into a pearl. It was guarded in an underwater coliseum in the ruins of a city at the bottom of the Pacific Ocean, and it was protected by two giantic eels.
When Captain Marvel sought the help of Amora the Enchantress to learn magic and protect herself from the Enchantress' future son Ove, the sorceress opted to make her resistant to it instead, and guided her to the location of the Heart of the Serpent. Since a magic barrier prevented magic users from entering the coliseum, Captain Marvel ventured alone and secured the pearl after killing its protectors. When leaving, Carol attempted to pass through the magic barrier with the hand she was holding the pearl with first. The barrier prevented her from crossing, causing the Heart of the Serpent to fall to the other side and away from her reach.
Amora recovered the Heart of the Serpent and returned to her home, where Captain Marvel returned her after escaping the coliseum. Explaining the nature of the Heart of the Serpent to Captain Marvel, Amora used a spell to liquify it and placed it in a flask. Amora turned against Captain Marvel after learning her true intentions, to kill Ove, and contacted him. During a subsequent fight between Ove and Captain Marvel, Ove noticed the hero attempting to reach the flask. Assuming its content to be some kind of time-travelling potion, Ove drank the flask to taunt Carol and was surprised to find himself unable to access his magic powers.
- The Heart of the Serpent's location was well documented in the Book of the Vishanti and, according to Amora the Enchantress, nearly every magician of note knows where it is.