Grave hags were first introduced in The Witcher: House of Glass graphic novel and they are territorial creatures. Their lairs resemble caricatures of human homes and are built near burial sites. They venture out at night to hunt, stalking straggling travelers or mourners too lost in their grief to notice the setting of the sun. On rare occasions hunger-driven grave hags will hunt during the day. They are less dangerous at such times, for sunlight weakens them considerably.