Here is another Old School Hack: the Fictive Way template: the berserker.
Jack Shear mentions this class here as a barbarian. He also notes my creation of this template in a post here, though I’ve just now gotten to putting it up as a post. I changed the class from barbarian to berserker because of this bit of text put up by Jack:
“Reflavoring: Of course, a barbarian character doesn’t necessarily have to hail from a barbaric culture. A barbarian might be a normal soldier who falls into a murderous rage in the heat of battle. Or perhaps a barbarian might be a normal man or woman who is sometimes possessed by the bloodthirsty spirit of a deceased maniac or murderer. “
If the most important thing is being crazy and killing stuff, then let’s focus on that instead of the cultural or geographic trappings. Hence, the template I present to you now.