A general of the former Neylern Kingdom in the northeast of the continent. He sought to restore Neylern to independence and former glory after Grangale conquered it in the war twenty years prior. He is very loyal to the royal family, respecting Vittorio as his monarch, and he is respected by the Neylern people. The soldiers still called him General, which the Grangalians disliked. At present, because of his age and illness, he cannot employ as much strength as he used to, but he was once heralded as the continent's mightiest Slayer (Knight Slayer).
In the war twenty years ago, Rockbein rescued Vittorio from the fall of the castle. Since then he raised and protected Vittorio since Vittorio's father the king was executed.
He wished to retaliate against the Grangalians but he is thwarted by the Peace Maintenance Brigade which represses acts of war. In secret, he and his subordinates investigated ruins to find other ancient weapons that could stand up to the Admonisher. Without the Admonisher, Neylern could wage war and take back their land from Grangale. He kept plans secret from Vittorio. He used his illness as an excuse to be absent from peace talks at the PMB. A Pothrad requested to meet Rockbein in secret and told him about a secret weapon. He gave orders to Elessa to research biological weapons and she acted as a spy in the Peace Maintenance Brigade for Rockbein's company. They found the secret ancient weapon and prepared to put it to use.
Zeonsilt's party, working for the Peace Maintenance Brigade, found out what Rockbein was plotting. Grangale also caught wind of this and confronted the PMB. They would prepare for war if Rockbein was instigating an attack. A Grangale soldier reported that a weapon was atop Mount Nostal, aimed at the Admonisher. Wolgainer urged Seldous to take action against this. The PMB would fire at Rockbein's weapon before Rockbein could attack the Admonisher. Krious, Melvina, Zeonsilt and Fanille ran to Mount Nostal to stop Rockbein. They would light a signal fire to indicate the Admonisher not to fire. They defeated Rockbein and his company and lit the signal fire, but Rockbein destroyed it. Zeonsilt's party had to flee from the mountain. The Admonisher's fire shattered a magical crystal that was acting as a seal. As a result, Ziekwalt was set free. Rockbein died in the blast.