The Neutralizing Potion is a southern potion that is used to neutralize anything, including other spells and potions. Only learned mermaids can use this properly, and they are taught about it when they get their Moon Rings. The potion is greenish in color and Sirena mentioned it smelling like cat-pee.
History[]
Nixie uses this potion to restore Poseidon back to its original form after he turned into Evie by accident by mixing squid ink and an unknown white powder.[1]