During Wassail, the kindred enters a berserk state in which the Beast takes total control over him. Such an event can occur whenever a vampire feels hungry and encounters blood. Hunger frenzies are most dangerous when a character actually feeds. Kindred who care about their vessels adopt various strategies to reduce the danger to their loved ones, such as never letting themselves become too hungry, or having a favored vessel drain blood into a bowl instead of submitting to the Kiss.
A vampire can slide from some kinds of frenzy to others. Yet, some forms of frenzy protect the vampire from others. Hunger frenzy is the weakest. A Wassailing vampire can be driven into a rage frenzy if he is kept from his prey, or a sufficient threat can drive him into Rötschreck. Self-preservation takes precedence over hunger, but sheer rage can overpower self-preservation if someone fights too hard to stop a fleeing vampire.
- Vampire: The Requiem Rulebook, p. 179