Terraria – How to farm the solar eclipse? If you can, what is the design

They are considered magic damage by the game. The terraria wiki states that the Terra Blade "is a Sword/Magic Weapon that fires sword-shaped projectiles." Also, if you kill a player with the projectile, it gives a death message that does not contain the word "terra blade" (or similar), rather it gives the name of the projectile, though this is not necessarily related

Download TEdit click Open then select your world then click is solar eclipse and press save wait for it to load and done.