Soul Whip

Soul Whip is a  weapon added in the 0.9.10 update. You cannot cast the rod for this item, as it will shoot the beam instead.

The Soul Whip does however require level 26 even though it isn't used for fishing.

This weapon can be converted into a dungeon item with wither essence. Once converted, it requires catacombs level 26 to be used in dungeons.