Terra Blade

The Terra Blade is a top-tier Hardmode Sword, currently with the highest base per-hit damage of any Sword in Terraria. It auto-swings, and fires a green sword projectile that costs no Mana or Ammunition and can pierce up to three targets.

Its best Modifier is Legendary.

Tips

 * With a Legendary reforged Terra Blade, Fire Gauntlet, Destroyer Emblem, Avenger Emblem, Mechanical Glove, and Warrior Emblem accessories all reforged with Menacing (+4% damage), and the Well Fed, Tipsy and Flask of Ichor buffs, As well as wearing the Chlorophyte Mask, Turtle Scale Mail, and Hallowed Greaves, the Terra Blade will have a base damage of 226 melee damage, making it possible to score critical hits for 600 damage.
 * The Terra Blade deals 13 more damage than The Horseman's Blade, despite being available earlier in the game. The Horseman's Blade can attain a higher damage rate due to its pumpkins that home in on the enemy (however the pumpkins don't attack other players in PVP situations).

Trivia
The Terra in Terra Blade may be a reference to Terraria itself, as it is a coveted weapon.
 * The Terra Blade's beam shape looks like the beam of the True Excalibur, but the beam has the green color of the True Night's Edge.
 * Similarly to Night's Edge, the Terra Blade has elements of (almost) all swords used to make it. The autoswing from Excalibur and Muramasa, the color of Blade of Grass, the light effects from Fiery Greatsword, and the shape of Night's Edge, as well as the beams mentioned above. The only exception is Light's Bane.
 * The Terra Blade itself seems to stand for Purity, or the unity of light and dark, since it takes the True Excalibur (a hallowed weapon) and the True Night's Edge (a corrupt weapon) to create.