I am working on a puzzle game. In the game the player changes the direction of gravity to solve puzzles. How do I use Blueprint to give the player the ability to do that? Thanks!
You cannot change the direction of (engine) gravity. At least not without changing the source code and compiling it (actually not so hard, but not everyone is a C++ programmer.
The simplest solution would be to mock the gravity, you have to disable gravity and apply your own force to all physics actors. You could make a parent class to ensure that all inheriting classes use this functionality.