Silas Cobb is one of Sander Cohen's former disciples, and one of four people you must kill and snap a photo of in order to finish Sander's quadtych (a type of artwork consisting of a series of four images) in Fort Frolic. Silas awaits you at Rapture Records, though you'll first have to deal with a group of Spider Splicers that the freak sets ablaze. Once it's a one-on-one battle, he'll continuously toss molitov cocktails at you while you're busy pummeling him with your weapon of choice.