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 23 even though it isn't used for fishing.

This weapon can be converted into a dungeon item with Wither Essence.

Usage
The Soul Whip can be used as a melee weapon or a ranged weapon.

When its ability is used, it shoots a beam in the direction the player is aiming. This beam has a parabolic trajectory of $$y=-\frac{8}{169}(x-6.5)^2+2$$, travelling forward 13 blocks and upwards 2 blocks. It deals its melee damage to all mobs hit. The ability does not consume mana, but has a hidden cooldown of 0.5s.

Holding right click will continuously activate the ability.

Essence Crafting
This sword can be upgraded with wither essence. Once converted, it requires Catacombs level 23 to use.

Tips

 * It's considered by some to be the best weapon for grinding Ghosts, as it provides a way of damaging them without getting into their range.