I was curious about the Unicorn magic used to protect the Mystery Shack from Bill Cipher. I know that Stan had the unicorn hair but when the Shack was attacked a blue dome would cover the house and there are symbols. I was wondering if they were a made up cipher for the show or if they all ready existed. I found a web site. http://bestcodes.weebly.com/gravity-falls-codes.html For the triangle in the circle it says fire of rotation. For the triangle with a little c on top it is the fire of circulation. The A is pulverise.
This is right after Bill Cipher has hit the house with his fist and is lifting up his fist. There might be a Solution Symbol on there too.