The Tesla cannon is a pre-War designed shoulder-mounted heavy directed energy weapon, designed to replace conventional anti-tank weapons. Based on Nikola Tesla's designs, the weapon entered limited production before the war and remains a rare sight in the wasteland. However, it remains a powerful tool in the hands of a skilled user, as the focused energy blast will not only deliver massive damage to the target, but the nature of the blast will also deliver a potent electric shock.
The modified Tesla canon employed by Lyons' Brotherhood of Steel is far more powerful than the pre-war Tesla canon. Discharging a large electrical impulse upon impact with a much larger area of effect. This explosive damage makes the Lyon's model far more suitable for anti-Vertibird use.
The Tesla cannon is a shoulder-mounted energy weapon that is powered by electron charge packs. This weapon has a high Strength requirement for its weight and the fact that it's a recoilless energy weapon. The sound of the Tesla cannon firing has also been changed from the one in Broken Steel.
The Tesla cannon is rare, especially so if players kill off the Van Graffs, thereby eliminating one of the only specialty energy weapon vendors in the game.
Inside of a High-Tech Gun case at Dry Wells. Lonesome Road
After completing the Honest Heartsadd-on, the cannon will respawn in the Brotherhood Safehouse footlocker.
Because the Tesla cannon uses 5 electron charge pack's per blast (which only accounts the fact that you fire once), it's only possible to get 1 empty electron charge pack from firing the Cannon, the same with all energy weapons that uses more than 1 cell per shot.
Due to it previously firing only 1 shot per reload, it ejects electron charge packs every shot which is strange considering only one is loaded. Also, the electron charge pack will not appear after one shot is fired, and the end of the cannon is retracted, but it still ejects another per shot.
The Tesla cannon can not be Jury Rigged with any other weapon, but can only be repaired with another exact copy or its unique variants. This is because there are no other shoulder fired energy weapons in the game.
A Tesla cannon was first planned for inclusion in Fallout: Brotherhood of Steel 2, as a "high-powered mass-cannon throwing tessellated plasma forward in an orgy of death and destruction", assembled from parts found during the game (including a Tesla coil).
Picking up the bulk energy cells above the cannon in the Brotherhood of Steel Safehouse before picking up the cannon below it will result in the cannon being picked up but will not show up in the inventory. The 8 WG will still apply however. Considering there is no known way to drop it, it will cause a permanent increase of 8 WG.
Because the Tesla cannon fires more than once per reload, in third person an electron charge pack will continually be ejected from the rear port, despite none appearing after the first shot.