How do I create a rock fall

Hi guys Im currently making a platform game and I have a few cutscenes but in one of them I would like a boulder to fall down and block the players from getting to the next level. Does anyone know how to implement this?

You use an instance variable, a trigger (an invisible sprite that changes the value of that instance variable) and move it accordingly.

alvarop I was thinking of doing something using the physics behaviour

Either use physics behaviour or have an animation of a boulder falling set on a sprite with bullet behaviour or just moving down Y axis.