[Gloom] Story Icon Question

I have Gloom 2nd Edition and three expansions. I've noticed that the expansions all have three additional story icons to those described in the instructions. Digging around the web I found that two of them are the mystery and horror icons from Cthulhu Gloom. The third icon (a dagger in front of some scrollwork) is not explained anywhere I can find.

Now the game is perfectly playable without the icon description, it really just adds a bit of color. But I am curious by nature and was wondering where it comes from and if there is a description of it anywhere.

I should note here that I am notorious for missing the obvious, so forgive me if I have missed something simple.

Appreciate any information.