It never seems like a full year between Fortnitemares as the unofficial start to the gaming holiday season has once again landed and is in full swing. To tie in with Halloween this year Fortnite has collaborated with the horror movie franchise Saw seeing the famous big-screen character Billy the Puppet being turned into a skin and the new Boom Billy weapon arriving and claimable. But how do you get Boom Billy, what is it and how do you use Fortnite’s latest weapon?