Bastard sword

A bastard sword, also called a hand-and-a-half sword, is a weapon that is in between a longsword and a greatsword.

Description
A bastard sword can be used in either one or two hands, thus giving it its name. It has a longer grip than a one-handed sword and has a shorter blade than a greatsword for extra precision in the strike. It is also more powerful than a longsword due to its increased weight. An average bastard sword costs 35gp and weighs 6lbs (2.7kg).

Use
Bastard swords are martial weapons normally used two-handed. They require extra training to use effectively with one hand. Therefore they are classified as exotic weapons in 3rd edition and 3.5 edition D&D when used one-handed.

Historical Comparison
Historically, the "bastard sword" was merely a form of Western European sword sized between the single-handed knightly or arming sword, and the larger two-handed longswords. The only functional difference is that the bastard sword could be readily wielded either one or two-handed (whereas the arming sword was designed for single-handed use and the longsword was most effectively used two-handed). Otherwise, these swords were wielded identically to their smaller and larger relations and would require no special training.

Notable bastard swords
Fatal Touch, the bastard sword of Kelemvor.

Ever Watchful / Vindicator, the bastard sword of Helm, Gedrin Thalavar and Kalen Dren.

The Moonsword of Eilistraee.

The acidic burst bastard sword of Graz'zt.