This is an actual game creator/editor program that allows you to create and customize whatever content you want to put into your own personal fantasy (no, not the dreaded genre itself) FPS game. It's quite complex and well detailed, but the graphics are rather substandard for an editor and sometimes the animations can get rather iffy when you implement them in the editor. It's from a not-so-well-known company simply called The Game Creators.
Here's the link to the site as well as a few links of Youtube videos demonstrating the program's capabilities:
FPS CreatorFPS Creator Tutorial VideoCreating Stories in FPS CreatorFPS Creator X10 VersionIt's heavily advisable that you must have a LOT of programming skills to use this editor.