When I played Dark Souls 1....I always use this sword, it is really good and the vision effects it has is spectacular everytime you swinging it:
A curved sword born from the soul of
Quelaag, daughter of the Witch of Izalith,
who was transformed into a chaos demon.
This blade inherits only the chaotic nature
of Quelaag, and has a unique speckled design.
Blade wielder erodes along with opponents.
Availability
Created by the Giant Blacksmith in Anor Londo using:
•Soul of Quelaag
•Any +10 Katana
•5,000 souls
General Information
•Bleed build up is 36 per strike
•Drains 20 HP per strike from the wielder
Chaos Blade 144/0/0/0
Bleed 300