If you haven't found it yet, try middle-clicking constant / function names to immediately open the script file where they're created. Super useful when navigating a large project. (So in this case, you could've clicked any of the monster_ constants to go to the file where they're defined, and that'd been the place to add new ones)
Also the ctrl-shift-F and ctrl-P hotkeys for opening global search / jump-to-asset can be useful if you know something's name but can't find it.