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"I've been working on this scrap-spitting beast. It's a dispute settler."
―Petra Forgewoman, upon giving the cannon to Aloy

The Oseram Cannon is an incendiary cannon capable of massive blast damage.


"Hold this thing steady while I give it a voice. Then we'll let it talk terms for us."
―Petra, finishing the cannon.

The Cannon was created by Petra Forgewoman, an Oseram inventor who had Aloy use it to defend the Oseram settlement of Free Heap as a test of the Cannon's capabilities. The waves of Bandits stood no chance against its incredible firepower. Petra later perfected the design and several Cannons were utilized to defend the Spire, mowing down waves of Corrupted Machines and Deathbringers.

Aloy, when first using the Cannon, commonly complained about the weight and recoil, and said that the weapon made her teeth chatter (Petra suggested adding a leather strap for the user to bite down on). She was rather perturbed to find out that the weapon could have malfunctioned.

When Aloy first used one, Petra warned her not to press the weapon against her hips "if you ever want to use those for--". Aloy cuts her off, so what the consequence would be is unclear. Given that Aloy is unafraid to discuss violence, it's possible Petra was referring to something more personal/intimate, such as sexual intercourse or childbirth.


"Ugh! Heavy! All I can do to hold it up!"
―Aloy, straining to lift the Cannon for the first time

Fired from the hip and capable of firing up to six rounds at once (each doing up to 600 damage), this weapon lobs devastatingly powerful bombs. It is a very advanced weapon with incredible range, as well as a special loading system that feeds bombs from a nearby ammunition basket. Holding down the trigger will load in one explosive at a time and releasing the trigger will fire all the loaded rounds, which explode on impact with the target.

The ammunition is stored externally in a basket, loaded with hundreds of glowing bombs.


  • Extremely high blast damage (the highest damage of any known weapon).
  • The few enemies it does not kill instantly are knocked flat and completely staggered.
  • Long range.
  • Scatters bombs to saturate and destroy everything in the target's area.
  • Unlimited ammunition (draws ammo from a seemingly endless basket).


  • Can only be used in two locations: Free Heap, during the Heap of Trouble Side Quest, and the South Meridian ridge, during the main quest The Looming Shadow .
  • Very dangerous to the user at close range due to the high power and large blast radius of the bombs.
  • Takes time to charge up multiple projectiles.
  • Like all pickup weapons, it slows Aloy down while carrying it. This is less applicable to the Oseram Cannon, as Aloy must stay next to the ammunition basket.
Ranged Weapons Blast Sling - ForgefireFW - Hunter Bow - IcerailFW - Rattler - Ropecaster - Sharpshot Bow - Sling - StormslingerFW - Tearblaster - War Bow
Melee Weapons Spear - Sylens' Lance
Stealth Weapons Traps - Tripcaster
Heavy Weapons Deathbringer Gun - Disc Launcher - Firespitter - Firestriker - Mine LauncherFW - Oseram Cannon - Ravager Cannon