is this really added faces and subtracting faces in the bge

The replace mesh actuator seems to be adding and subtracting faces.Here is the blend.Press w to make hole.Press x to
fill hole.Then press the spacebar to drop cube.

Attachments

dig hole.blend (470 KB)

What’s the problem with your blend? It behaves as you described…

I just wanted to demonstrate something that can be done with the bge.