Berserker is the Second Fist of Ragnarok. He is often seen chewing bubble gum and hardly ever speaks. He has quite a calm disposition despite all the damage being done to Ragnarok. It is revealed that Berserker did not once study martial arts, but simply has a natural talent for fighting. He is a Dou type fighter, and can go into "Berserk Mode", unleashing more power. Berserker is said to be the most fearsome fighter in all of Ragnarok, and Loki even believes that he could be a better First Fist than Odin (though Loki may have simply said it in order to plant a seed of betrayal in Berserker). However, Berserker shows no interest in becoming a leader for any gang, and is actually afraid of fighting Odin, believing that the latter is much stronger than he is.
Later, when Hermit defeats Berserker in the final battle, he is unwilling to admit defeat and attempts to continue on, despite his injuries. However, Kenichi tells him that one should not be ashamed of defeat because one learns more from it, whereby he stops trying to fight, but is finished off by Odin. His current condition and whereabouts are unknown at this time. However, in chapter 344 a silhouette of what appears to be Berserker can be seen with Yami.
He is named after Berserkers, Norse warriors. His sleeveless jacket also has Norway's flag pattern. He displays traits similar to the Nordic Berserkers of ancient times, such as displaying a furious battle rage in his attacks when aroused, as well negating feelings of pain through an adrenaline rush that enables him to ignore his injuries and continue fighting.
In the DfoD arc and the YOMI arc, he is the only accounted member of Ragnorak, the others having defected to Shinpaku or lying low (Odin joins YOMI, while Loki's sihoulette has been seen in an informant message to Nijima). However, a recent figure in sihoulette as one of the three individuals chosen by Kensei to take up his experimental disciple program bears a great similarity to Berserker, though it is still unknown whether or not this is true.