Burning Blade is the best sword for farming. This blade does 15% extra damage to all monsters.
To get this weapon type /join lostruinswar in your chat bar. Now go to screen 7 and kill
Level : 25
Difficulty : 3 Stars
Total HP : 82,103
This blade is non member and 0 AC. You can keep it in your bank if you don't need it. This blade has only 1% drop rate confirmed by Aranx. You might have to kill the monster several times to get the drop.
Special thanks to Samuel Matta.