The Mace
The mace was developed once swords could not pierce certain armor. Maces are solid metal spiked balls on the end of a wooden or metal handle. The mace could inflict great damage on heavily armored knights without having to go through the armor. The impact from the weapon dented the armor, hurting the knight inside it, causing bruises, broken bones, and internal injury to organs. A mace could be swung at the head of an armored knight causing concussions and brain damage. The mace soon became a valuable weapon to knights.
http://www.akban.org/wiki/index.php/Mace_%28club%29
http://www.historicalweapons.com/otherweapons.html