Broken Broadsword is a Tier 1 weapon and the starter broadsword obtained in the introduction mission. It's the first weapon players will obtain and also the first Unique Weapon - a weapon with fixed stats and abilities; all copies of the weapon are identical. It's required to pass by a tentacle blocking the player's path to their ship.
If players retain this weapon they'll later have the opportunity to upgrade it into one of the most powerful broadswords in the game, the Protector's Broadsword.
The weapon's long description reads as follows: "A very nice sword in very poor condition."
True to its name, the Broken Broadsword is not a very good weapon. The primary ability, the typical broadsword melee combo, only has a base DPS of 7.5 and a 1x-damage fire time of 0.8 seconds (i.e. 1.25 1x-damage attacks per second), producing a 1x-damage hit power of 6. In comparison, tier 1 common generated broadswords have a base combo DPS ranging from 10 to 11.
Not everything about this weapon is bad, though. The Broken Broadsword comes with the Spin Slash alt ability that can sometimes appear on generated broadswords. Due to the way that alt abilities function, the Broken Broadsword's Spin Slash has the same power as any other tier 1 broadsword's Spin Slash.