Lystent
Terrarian
I actually was lucky enough to get the demon scythe while it was still useful... I only got 2-3 others since then, in all of my 800 hours.You know what's the worse? Rare weapon drops. By the time you get it, you are probably already using something better.
A good example is the demon scythe. It rarely drops from demons, and if you are fighting demons you are near hardmode, where you can get a better magic weapon pretty early.
Same for medusa heads; they drop from a rare hardmode enemy with a 1% chance, and by the time it finally drops you are probably wielding something better.
I don't mind accessory drops, but rare weapon drops are annoying for this reason.
Edit: It has good dmg, and good rate of fire. It just eats lots of mana. Ideal during the time when I first got it when I had a mana flower and a couple stacks of mana potions (before they added the debuff).