God's Stone of Retaliation is a rare mineral material that can make most witches' abilities powerless, but useless against Extraordinary witches.
This stone in a raw state is extremly tough and can resist to cuts and gunshots, but is fragile once extracted.
Can be manipulate only in soaking it with either witches or demons blood, it will then melt.
Nightingale mentioned that In the Mist they look like black holes.
Despite Stone's reputation as absolute anti-witch weapon, non-Extraordinary witch Isabella could disable its effects.
These stones were sold by the Church, but because of the high prices, only nobles nobles could afford even the tiniest piece of stone.
Nightingale used to put a God Stone of Retaliation under Roland's pillow.
Church used to pile up God stones in the churches.
A God's Stone of Retaliation's vein is located under each Holy city, established by the Witch Federation.