A bestiary entry can be added by reading In Beast's Clothing.
- Ulfhedinn? What's that, some kind of fish?
– Professor Artibus Joannes Rack, geographer, disappeared during a surveying expedition in Skellige
- Ulfhedinn are a breed of werewolf found mainly in Skellige. The harsh and barren conditions of the isles might explain why they primarily hunt men and are stronger than their continental brethren. Older and particularly dangerous ulfhedinn are called vorefs. Only a few daring warriors in Skellige history have managed to defeat an ulfhedinn, and each of them is commemorated in ballads as a hero to this day.
- Like werewolves, ulfhedinn and vorefs are active at night, particularly when the moon is at its fullest. Fast, strong, and amazingly resilient, these creatures kill with disturbing ease. Silver blades should be brought against them, as should Devil's Puffball. Take note that when near death the ulfhedinn becomes particularly dangerous and will attack with doubled fury, while calling on wolves to come to its rescue.
These breeds of cursed ones are some of the fastest and most lethal. They can leap great distances at such speeds that it can be a challenge defending against them. Yrden is of great use in avoiding these attacks. Counterattacks against a werewolf or ulfhedinn can be difficult to time. It is best to use footwork and evade them, using dodges and roles. When possible, use Igni.
Setting these foes alight can force cursed ones to stay still long enough to score critical strikes on their flanks. Fire, bleeding, and poison effects can be used to slow the regeneration of these creatures. Avoid fighting werewolves in tight spaces if at all possible, since the speed of their assault can quickly overwhelm even high skilled witchers. Werewolves have incredible reach, and you want to have space to work with while fighting them.
Explosive bolts for a crossbow can be useful at dealing fire damage, should the werewolf be caught at range. Watch for the dual overhead claw swipe; it cannot be parried and causes grievous wounds and bleeding. Near death, ulfhedinn become extremely dangerous, striking with increase strength. They can even call upon a pack of wolves for assistance.
- Historically, the Úlfheðinn were Norse warriors who fought dressed in wolf clothes in a state of trance, after having ingested cocktails of beer and amanita muscaria. They were akin to the Berserkers.
- In the The Witcher, there exists a large Wolf called Voref, which unlike other wolves is weak against silver.
- There are two Ulfhedinns in the game, one is in In Wolf's Clothing quest, the other one is at the right side of the lake near Fornhala village, near the monster nest.
- The name is probably the Icelandic name Úlfhéðinn, which derives from two names: Ulf, meaning "wolf" and Heðinn, meaning "jacket of fur or skin".