The Brocken Clan is originally human, but at adulthood a young man is given a skull badge, or "Totenkopf." This turns them into a Choujin as evident by the Swastikas (now Death's Heads due to Japan's increasing cultural sensitivity) on their shoulders. Apparently, the Clan is known for their technique the Red Rain of Berlin, and have no devastating finishing holds, instead relying on moves to wear the opponent down. The Brocken Clan has been hinted as being involved in all of Germany's wars, and have a very militaristic lifestyle. They are also recorded as not standing out much in the Choujin World, some have even said the Brocken Clan is "cursed." It can be assumed that, if Brocken Jr. does not have a child and the English anime is wrong about Jade and Brocken Jr.'s relation, the Brocken Clan will have died out in terms of blood-relation with Brocken Jr.
Brockenman--+--Unknown Female | | Brocken Jr. | | Jade (adopted)