Hi night_tig3r_13,
If you are talking about the BSP additive and subtractive geometry, they can’t be referenced by blueprint and can’t be manipulated at run-time.
However here is one possible solution, you could create a material with Location Based Opacity and add that to a blueprint. Here is a tutorial on how to set that up.
Another way would be to create the effect in a modeling program by animating it.
TJ