Backbiter

Backbiter is Luke's sword which, in The Battle of the Labyrinth, is revealed to be a modified version of Kronos' scythe.



Description
Backbiter is a double-edged sword made up of two metals: tempered steel, and celestial bronze. This means that it can wound mortals and immortals both and sever their soul, which makes it really similar to Stygian Iron, probably more powerful. Apparently, Backbiter is also capable of "slashing" open portals, as seen in the final scene in which Luke and Percy meet in ''The Lightning Thief. A'' long sword for one hand, described as being a foot longer than Percy's sword, Riptide (in other words, 4 feet long).

Kronos' scythe has the same bronze-and-gray glint as Backbiter, but it is a much larger weapon, with a six-foot-long blade curved like a crescent moon...but also thin for its length. Adding in the length of the handle, the scythe is a large, long weapon which generally require two hands to use. Kronos is extremely proficient with it, and has a nuanced fighting style taking advantage of the scythe's quirks, such as its curved blade and long reach.

Naming
"Luke called this Backbiter. An apt name, as it will surely bite back."

- Kronos

The name Backbiter was named by Luke, saying it can hurt both Mortals and Immortals, and fatally wound a demigod. It is possible that Luke named it this from the phrase "Stabbed in the back".