Flamelash

Flamelash is one of several Magic Weapons found throughout Terraria, obtained as a rare drop from Bone Serpents. When cast, it launches a mouse-controllable ball of fire, which also emits a small light radius, and gives off embers which fall through the ground. As it costs only marginally more Mana to cast, but inflicts more damage, it is considered a higher-tier version of Magic Missile. It can hit weaker monsters twice, such as slimes, without causing the fireball to dissipate. (Stronger monsters need confirmation)

Here is a guide on using Flamelash

Tips and Strategy

 * Because it emits numerous amounts of light particles, it can be used as a "surface scanner" because the particles fall deep within the ground, helping find valuable ore in the ground that otherwise would remain unseen.
 * Because of its controllable nature, this weapon can be effectively used to safely clear out overgrown dungeons.
 * Another use for this very versatile weapon is using it to "snipe" the head parts of worm enemies. To do this simply use the weapon and hover the fireball over the area of the ground you expect the worm enemy to come out of and if your aim is right you can guarantee damage to that oh-so vulnerable spot of worm enemies.