1. Toad: This is explicitly mentioned, and the witches use it to create a potion for their prophecy.
2. Eye of Newt: This is also explicitly mentioned, again as an ingredient in the potion.
3. Wolf's Bane: This is not explicitly mentioned, but is commonly interpreted to be the third ingredient, based on the following lines:
> "Double, double toil and trouble;
> Fire burn and cauldron bubble.
> Fillet of a fenny snake,
> In the caldron boil and bake;
> Eye of newt and toe of frog,
> Wool of bat and tongue of dog,
> Adder's fork and blind-worm's sting,
> Lizard's leg and howlet's wing,
> For a charm of powerful trouble,
> Like a hell-broth boil and bubble."
These lines are a list of ingredients, and "wolf's bane" fits the rhythm and meter, creating a sense of alliteration with "blind-worm's." However, there is no definitive proof that "wolf's bane" is the intended ingredient.
It is worth noting that the witches are deliberately using ingredients that are associated with darkness, poison, and death to symbolize their own dark magic and their power over fate.