Like the berserkers, they performed chants and ritual prior to battle to get in a "Berserker Rage", when, through adrenaline, they became much stronger (possibly upwards of ten times stronger than normal. Anymore and their joints and ligaments couldn't take it) and faster, became immune to pain, and bled less.
Unlike normal berserkers, these warriors wielded no shields. They eventually merged with the Berserkers in name, yet continued to prefer their own methods (wolf skins, etc).
It was said that to kill an Ulfhednar, you had to crush their heads. Thus like zombies, you have to go for the brain. A heavy weapon like a club or mace could do the trick, but in reality, other methods could be used (decapitation, stabbing the spine to invoke paralysis, etc).
In a remote region of Iceland, near several barren hills, a large gathering of people have been filming a movie. For weeks they have struggled against weather and script changes, and now most are asleep. In one of the trailers, five great and terrible black werewolves move all around and within one actor's trailer, trying to find the man who disgraced their kind on the silver screen.
On the side of this trailer, the name "Taylor Lautner" tis' written. Five long, deep claw marks cover the name.
As the werewolves rummage through the trailer and raid the fridge, the alpha male catches a scent, an unusual human scent. Then five eerie howls pierce the night, and the werewolves stop their trailer trashing and move outside the trailer. Their teeth are bared, their mighty paws stomp the ground. As the howls occur again, five unusual humans appear, wearing wolf skins, having black pigment covering their bodies, and bearing Medieval Viking swords and other weaponry. The warriors are startled by the appearance of the werewolves, and raise their weapons in rage, almost foaming at the mouth.
Two of the warriors charge. The Alpha male werewolf motions two of his top werewolves to incercept...
The first werewolf leaps 40 feet towards his opponent, but the Viking Ulfhdnar raises his spear and braces himself. The wolf opens its mouth and growls, but as he nears his leap's end the spear pierces the top of his mouth, entering the brain . Nearby, the other Werewolf engages his Ulfhednar, tearing his chest and belly apart with two mighty strokes. The Ulfhednar, to his surprise, does not scream with pain or pass out. The Viking warrior cleaves the werewolf's skull in two with a battle axe . The sam warrior throws his axe at another werewolf nearby, penetrating the chest. The alpha male werewolf leaps towards a third charging Ulfhednar. With one paw swipe the warrior's head flies . Before the remaining 4 Vikings use their numerical advantage the last werewolves run deeper into the night. The Viking warriors persue, but the warrior with the torn chest is tripping over his intestines, and has lost a lot of blood. As he trips and falls for the third time, he looks up and sees a huge black werewolf foot, which is tapping the soil. With a quick strike to the heah, the Ulfhednar fights no more.
Two of the Ulfhednars search for the werewolves under the starlight, several yards from the trailers. As they spit and curse in icelandic, the last werewolves group together, and the alpha male gives the signal. Immediately the alpha male leaps into one of the warriors, knocking him off his feet, while the other warrior is jumped from behind. While the alpha male faces his rising norse opponent, the other wolf skin warrior is being torn to shreds by the other werewolf. Though the other werewolf is amazed at the abnormal strength of his foe, he easily rips him to bloody ribbons . The other warrior, bearing two battle axes, charges at the alpha male. The werewolf, however, has the advantage in speed and strength, and within a few moves the Viking is headless, armless, and down . The alpha male exhales, but then hears a sickening thud. Turing his head around, he sees his comrade, staggering, a spear sticking through him. The werewolf falls.
The last Ulfhednar, the captain of the wolf skin warriors, appears, and prepares to engage the last werewolf. He bears two mighty Viking broadswords and chants a prayer to the Norse allfather. The Werewolf sneers, his muscles rippling his skin. The werewolf runs on all fours at the Viking, faster than a race horse. He stops and rears up, his paws about to swipe. The Ulfhednar thrusts with his blade into the chest of the werewolf. He loses his left arm to a countering paw slap, but wields his other sword onto the werewolf's neck, severing the head .
The Ulfhednar leans down, picks up the head, and raises his sword into the air, yelling "For Odin!"