Using looting on a mob seems to always, if not mostly, drop duped version of the item. Normally, it is a "ghost" item that cannot be picked up, but if a user stands close enough upon mob death, will gain the duped items as well. For example, I got 3 swords with same enchantments, name, damage value, etc from one zombie when I killed it very very close to me(on the block next to me). I replicated this multiple times on bows, magic items, jems, and more, throughout builds 215, 218, 224, and 238.

Perhaps it can be fixed through adding a "blocked enchantment" option in tiers.yml? Seems it would be simpler than redoing the looting effect code to stop duping of items.

It's not an issue caused by our code (we've looked around and inquired), it's a side effect of Bukkit/CraftBukkit and Minecraft code.

We will look into it more, however.

Build #239 Fixes the issue with ghost drops.