Chaos Sword

The Chaos Sword, or Sword of Chaos, is a powerful weapon encountered in Ultima V.

Description
Rumors had reached the Avatar that Lord Blackthorn possessed a special sword, stored in a chest covered in human skin, deep within the bowels of the Palace of Blackthorn. The forces in this sword were said to be so horrible that it would force the wielder to slaughter his or her own friends in a fit of madness. The wise Avatar resisted the temptation to wield this horrid weapon.

It is unknown what became of the sword after the events of Ultima V.

Trivia

 * According to the Prima Guide to the Ultima Collection, the Sword of Chaos has a 99(!) damage rating, which is equal that of to a glass sword.
 * The Chaos Sword disappears after the first time it is used in combat.