A bec de corbin. The name is Old French for "crow's beak". Similar to the Lucerne hammer, it consists of a modified hammer's head and spike mounted atop a long pole. The bec de corbin was used primarily with the 'beak' or fluke to attack instead of the hammer head. The hammer face balancing the beak was often blunt and the beak tended to be stouter; better designed for tearing armor.
Armor 15th century, military campaign armored German light infintry, mercenarie, German flail, Bec de corbin, gambeson, Chainmail shirt, jack chains, chainmail gloves, Brigandine upper leg armor, open face sallet with Aventail. David Bobrink