Fierce attacks are great, as they do lots of damage, and never run out of ammunition. The problem is sometimes with their range and the frequency of their use. The skill Onslaught of Claws takes care of that. It will increase the rate that you can unleash your fierce attacks by 70%. Since the Berserker is as handicapped at ranged combat as the Commando is at melee, fierce attacks are a great way to make up for this deficiency. When combined with the Human skill Desire to Overcome, these attacks have quite an impressive range, allowing the Berserker to deal with polarities without poisoning, burning or freezing himself.