Dak'kon's Zerth Blade

Dak'kon's Zerth Blade is an enchanted katana +2, which inflicts 1d10 +2 points of damage and has +2 thaco bonus. It allows the wielder to memorize one extra lvl 1, 2, 3 and 4 wizard spells, which adds very much to the value of the blade. It has a weight of 4 lbs and a speed factor of 2.This weapon can be wielded by all classes which are allowed to wield katana's, but only bards and fighter / mages benefit from these extra spellslots. Dak'kon and The Nameless One are characters from the computer game Planescape: Torment, which set in the same world as this game. This item appears in Baldur's Gate II: Shadows of Amn.

In-game description
"This sword was the weapon of choice of the famous githzerai Dak'kon.  Dak'kon was killed by a powerful entity while working for a creature known as the 'Nameless One'."