FPS Creator X10 is described as 'Prepare to enter the exciting world of game making, as you create entire worlds from your imagination and populate them with anything you want. Add in your very own squad to fight by your side or go it alone'. There are more than 25 alternatives to FPS Creator X10 for a variety of platforms, including Windows, Linux, Mac, Android and iPhone. The best alternative is Unity. It's not free, so if you're looking for a free alternative, you could try GDevelop or Scratch. Other great apps like FPS Creator X10 are CRYENGINE (Free Personal), Ren'Py (Free, Open Source), RPG Maker (Paid) and Cocos2d-x (Free, Open Source).
GDevelop is an open-source game making software designed to be used by everyone. Any kind of 2D games can be created with it and no programming skills are required to get started. Logic of games are made using visual events.
Adventure Game Studio (AGS) - is the IDE and the engine meant for creating and running videogames of adventure (aka "quest") genre. It has potential, although limited, support for other genres as well.