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 with Backbiter sheathed.

Luke with Backbiter sheathed.

Backbiter is Luke Castellan's half-Celestial Bronze/half-steel sword which, in The Battle of the Labyrinth, is revealed to be a modified version of Kronos' Scythe.

Description

 with his , the original form of Backbiter.

Kronos with his scythe, the original form of Backbiter.

Backbiter is a double-edged sword made of two metals: tempered steel and Celestial Bronze. This means that it can wound or kill mortals, demigods, and immortals alike and sever their souls, which makes it similar to Stygian Iron. Apparently, Backbiter is also capable of "slashing" open portals, or travelable rips through space and time, as seen in the final scene in which Luke and Percy meet in The Lightning Thief. It is a long sword for one hand, as it is described as being a foot longer than Percy's Riptide, or four feet long.

In The Battle of the Labyrinth, Backbiter is broken down and reforged by Telekhines in the forge in Mount Saint Helens. 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 is also thin for its length. Adding in the length of the handle, the scythe is a large, long weapon that generally requires two hands to use. Kronos is extremely proficient with it, and he has a nuanced fighting style taking advantage of the scythe's quirks, such as its curved blade and long reach, but also showing skill in using it in its original form.

In The Last Olympian, Kronos reverts his scythe into Backbiter when he challenges Percy to a sword duel, but Percy manages to disarm the weapon where Hestia superheats it to prevent Kronos from retrieving it. The sword eventually melted into a pool of molten metal after Kronos's destruction.

Uses

Backbiter, in its sword form, is used predominantly for close-range warfare and hand-to-hand combat. It probably weighs around as much as Riptide and can be wielded in one hand along with a shield for the purpose of versatility. However, it is used primarily and is more effective when used with both hands. Because it is made of Celestial Bronze and tempered steel, it is capable of physically harming mortals and monsters alike, making it very dangerous. Because it is, in actuality, the weapon of the Titan Kronos, Backbiter is extremely powerful, as when Luke uses it to battle Thalia at Mount Othrys, the clash of both their weapons - in Thalia's case, Aegis - creates an explosion of vicious energy.

Naming

Backbiter, Luke called it. An appropriate name. Now that it is reforged completely, it shall indeed bite back.

–Kronos, after he was first resurrected in The Battle of the Labyrinth.

The name Backbiter was chosen by Luke who said it can hurt both mortals and immortals, and can fatally wound a demigod. It is possible that Luke named it this from the phrase "stabbed in the back." When the sword was reforged into the shape of a scythe, Kronos claims that the sword will bite back at the Olympian gods.

Percy Jackson and the Olympians (TV series)

"Easy. I don't wanna fight. This is what I wanted to show you. This... is our way out."
"Way out of what?"
"Camp. And their control. Backbiter can open secret doors. We can stay on the run as long as it takes.

Luke Castellan and Percy Jackson, in "The Prophecy Comes True".

Backbiter is Luke Castellan's half-Celestial Bronze/half-steel sword.

Uses

Backbiter can open portals. Using it, Luke opened a rift between Camp Half-Blood and the outside world by carving a V shape onto a stone pillar and then fully opening it into a portal once Luke drew a line across the middle. Luke has also used these portals as a personal teleport, as seen when he transported himself from the Princess Andromeda to Polyphemus' island.

Season One

"The Prophecy Comes True"

Backbiter in the TV series adaptation

Backbiter in the TV series adaptation

After Luke is revealed to be the true Lightning Thief, he draws Backbiter, but uses it to open a portal out of Camp Half-Blood while trying to convince Percy Jackson to join him. Percy refuses and draws Riptide instead and the two demigods fight until Luke eventually overpowers Percy. However, after Annabeth reveals herself, Luke abandons the fight and flees through the portal that he had opened which closes behind him,

Trivia

Items
Personal Weapons: Riptide | Annabeth's Knife | Backbiter | Master Bolt | Poseidon's Trident | Nico's Sword | Thalia's Spear | Aegis | Ares' Sword | Ares' Shield | Caduceus | Apollo's Golden Bow | Silver Bow | Artemis' Knives | Hades' Sword | Hades' Staff | Kronos' Scythe | Ivlivs | Katoptris | Hazel's Spatha | Frank's Spear | Reyna's Spear | Juno's Gladius | Annabeth's Sword | Sumarbrander | Gungnir | Gjallar | Mjolnir | Gríðarvölr | Khopesh | Mallory's Serrated Knives | Meg's Twin Imperial Gold siccae blades | Thyrsus | Hecate's Torches | Minotaur's Axe | Leroy's Sword | Tyson's Javelin | Alex's Garrote Wire | Piper's Sword
Magical Items: Annabeth's Yankees Cap | Helm of Darkness | Pandora's Pithos | Winged Shoes | Golden Fleece | Flying Chariot | Golden Apple | Apples of Immortality | Greek Fire | Hermes' Multivitamins | Nectar and Ambrosia | Stygian Ice Whistle | Keys of Hades | Leo's Magical Toolbelt | Serapis' Staff | Magic 8 Ball | Arrow of Dodona | Pig Ball | Mechanical Spider | Angel Statues | Athena Parthenos | Chiron's Wheelchair | Diocletian's Scepter | Flaming Dodgeball | Gleipnir | Poseidon's Pearls | Queen Hippolyta's Belt | Mistletoe Arrow | Frank's Stick | Expand-o-Duck | Caligula's Caligae | Ran's Net | Rune Stones | Nábrók | Pomegranate | Chains of Prometheus
Spoils of War: Minotaur's Horn | Medusa's Head | Kampê's Scimitars | Nemean Lion's Pelt | Gorgon Blood | Cornucopia | Lydian Drakon Hide | Phineas' Robe and Slippers | Triptolemus's Almanac | Odysseus' Astrolabe
Items: Camp Necklace | Chameleon Armor | Daedalus' Laptop | Golden drachma | Denarius | Red Gold | Mark of Athena | Archimedes Sphere | Thalia's Shield | Video Shield | Wristwatch Shield | Golden Mango | Sibylline Books | Letter of Recommendation
Ships Amos' Boat | Argo II | CSS Birmingham | Egyptian Queen | Julia Drusilla Yachts | Pax | Queen Anne's Revenge | Reed Boat | Naglfar | Gorgyra's Canoe
Blessed Metals: Adamantine | Celestial Bronze | Imperial Gold | Stygian Iron | Bone Steel