The Railgun charges up and fires a beam, similar to the Rifle. It initially has 2 shots, and has 3 after upgrading it. Each shot does 7 DMG. The Drifter is immobile while the Railgun is charging, though he can adjust the gun's aim. The Railgun's fire does not penetrate enemies.
The Railgun can be found in the Barren Hills, at the end of the dungeon past the 8-Module door.