Avatar Vanquishing Potion

Avatars can be vanquished by an ancient egyptian potion. Though none of the ingredients are known , it is a very special potion (as stated by Zankou in "Charmageddon"). The potion was created originally by Anubis at first and then by the forces of both Good and Evil (presumably by witches and demons). The Good and Evil energy created a Neutral effect which gave the potion the ability to kill Avatars. When the potion is thrown and breaks it releases a black-grey smoke, which then enters the Avatar through both the mouth and nostrils, killing them almost instantly.