The bec de corbin is a polearm very similar to the lucerne hammer, but the hammer head is slightly blunter and the spike is stouter and more hooked. You primarily attack with the spike.
You gain a +2 bonus on combat maneuver checks to sunder medium or heavy armor with a bec de corbin.
Advanced Player’s Guide. Copyright 2010, Paizo Publishing, LLC; Author: Jason Bulmahn.