I have looked at many, many lists of Halloween and "spooky, scary" type name lists and I have to say I'm surprised I haven't come across this one on any lists! You see plenty of word names such as Shadow, Shade, Raven, Tempest, Thorn and more, but no Gore.
Gore is well qualified to make it onto any list of Halloween baby names. The dictionary lists a few different definitions for the word gore, two in particular which are gruesome enough to earn Gore a place on any list of scary names. One is "blood that has been shed, especially as the result of violence", as in horror movies featuring blood and gore. Another is "to pierce of stab with a horn or tusk", i.e. to be gored by a bull. Which if you've ever seen the Running of the Bulls in Pamplona you'll know is a sort of horror itself.
Grisly meanings aside, Gore came into use as a name in much the same way many names have come into use - firstly as a surname, taken from the place name or landmarks which identified where a family lived. Gore came to use in Britain during the Middle Ages, derived from the old English word 'gara' meaning "a small, usually triangular piece of land". These days people bearing the last name Gore can be found worldwide, with some well known bearers being American footballer Frank Gore, 'It's My Party' singer Leslie Gore; and former US vice-president and Nobel Peace Prize winner Al Gore.
Gore is very rare as a first name, although at least one famous bearer was inspired by their family tree. American writer and intellectual Gore Vidal was born Eugene Louis Vidal but became Eugene Louis Gore Vidal when baptised as it was his mothers maiden name. At the age of fourteen he reportedly dropped Eugene Louis because he "wanted a sharp, distinctive name, appropriate for an aspiring author, or a national political leader". His father already went by Gene, and so he decided to become Gore. It certainly is sharp and distinctive.
The other famous Gore - director Gore Verbinski - wasn't originally named Gore either. The director of 'The Ring' and the first three 'Pirates of the Caribbean' movies is actually a Gregor, choosing to go by Gore.
Despite having worthy namesakes to serve as inspiration, I think Gore really is most usable as a nickname. It is a bold and sharp name, and most people would immediately associate it with blood and horror; so you'd need to be a strong, charismatic character to do it justice. Choosing a name with Gore as a nickname means you could choose to use it if or when you felt comfortable to do so. Or if your child is a Halloween baby it could be a nickname that is only used at that time of the year, in much the same way 'The Simpsons' changes the names in their credits for their Halloween specials.
On that note, I'll end with a list of boys names that lend themselves to the use of Gore as a nickname: