The Fission is a futuristic shotgun with black and white frame and neon green glowing parts. It has six glowing cylinders on top of the receiver that jump up and down while the gun is operated and make a loud buzzer noise when one is forcibly pressed down, as seen during inspect animation. Although it appears like it would have pump-action mechanism, it is actually semi-automatic - the handle under the receiver is actually a magazine release mechanism that, when pulled backwards, violently ejects the top-mounted cartridge magazine containing green substance.
- The front sight is located in very awkward position where it would realistically be impossible to be used, as it would always be obscured by the magazine.
- A fission in nuclear physics or chemistry is a process where atom's nucleus splits into smaller parts.
- This weapon is inspired by plasma weapons in Fallout 4.
- Fission is the only weapon in the sci-fi set that is reloaded by manually inserting a new ammo container into the weapon.