In the game Terraria, the Broken Hero Sword is a rare crafting material used to create some of the most powerful melee weapons in the game. It is a crucial component in crafting the True Excalibur, True Night’s Edge, and Terra Blade weapons. The Broken Hero Sword is obtained by defeating Mothron, a rare enemy that spawns during the Solar Eclipse event.

The rarity of the Broken Hero Sword can be attributed to a few factors. First, Mothron itself is a rare enemy that only spawns during the Solar Eclipse event. The Solar Eclipse event itself is a rare occurrence that only happens randomly after defeating the game’s mechanical bosses. This means that players must have progressed significantly into the game to even have a chance of encountering Mothron and obtaining the Broken Hero Sword.
Furthermore, even if a player does encounter Mothron during a Solar Eclipse event, there is no guarantee that it will drop a Broken Hero Sword. The drop rate for the Broken Hero Sword is only 25%, meaning that players may need to defeat Mothron multiple times to obtain the required amount of Broken Hero Swords for crafting the desired weapons.
To further complicate matters, the Solar Eclipse event itself only lasts for a limited amount of in-game time. This means that players must be prepared to face Mothron and defeat it quickly to have a chance of obtaining the Broken Hero Sword. Failure to do so may result in the event ending before the player has had a chance to obtain the necessary materials.
Given all of these factors, the Broken Hero Sword can be considered a very rare item in Terraria. Its rarity is compounded by the fact that it is a required component in crafting some of the most powerful weapons in the game. This means that players who wish to obtain the best gear and weapons must be willing to invest a significant amount of time and effort into obtaining Broken Hero Swords.
In conclusion, the Broken Hero Sword is a very rare item in Terraria due to a combination of factors, including the rarity of the enemy that drops it, the low drop rate, and the limited time window in which it can be obtained. Players who wish to obtain the most powerful weapons in the game must be prepared to invest a significant amount of time and effort into obtaining the necessary Broken Hero Swords.