Le Fusil Terribles

The Le Fusil Terribles is a unique weapon in Fallout 4. It has the 'Violent' weapon prefix.

Characteristics
25% increased damage and limb damage, but has more recoil

Weapon modifications
Extended mag Bayonet Full auto receiver Short barrel

Variants
Combat Rifle

Locations
Found on top of a yellow lootable wooden crate, just as you enter the captain's cabin in Libertalia. The lootable wooden crate is straight ahead from the entrance, next to a lit lantern. It's also found during the Synth Retention quest (during The Institute quest-line), immediately after the cut-scene with X6-88.

Behind the scenes
The name of the weapon might be a reference to the 1950 french movie "Les Enfants Terribles"