Purple Clubberfish

Roughly every other hit scrambles the target, and a confused enemy turns around and walks away instead of at you. Against a pack of ground enemies that is close to a stun, since they spend the whole debuff wandering off in the wrong direction. Fliers get knocked off their approach line too. None of this applies to other players, so do not plan a duel around it.

It comes out of a Corruption fishing hole, and your odds climb sharply as your fishing power goes up, so sort out decent bait and a real rod before you start grinding. The payoff is a broadsword that beats most of what you can craft at that stage of a Corruption world, without touching the Underworld.