How could I design a home god and a sacred symbol?

One of my players is playing a dnd blood hunter beyond the site. He wants his character to be the subclass based on the ghost hunter and that his background story be that he grew up in a family / group of ghost hunters. All those who worshiped or looked at one or two gods and I only remain blank in the design of such a pike and associated sacred symbol. How could it be a sacred symbol for that kind of thing?