Frenzied Berserker 

The Frenzied Berserker is an Organizational Class, meaning that taking a level of Frenzied Berserker on this server indicates that the character is a member of an organization. The organization in this case is going to be a nomadic tribe of some sort.

 

Nomadic Tribes will wander from place to place as Barbarians. The elite most Barbarian nomad should be considered the Frenzied Berserker.

 

According to NWN2 documentation, Barbarian is the only class that the Frenzied Berserker will benefit.