I originally posted this in my first thread, but no one read it, so i'm posting it here instead. But before I ask the question, I shall elaborate.

I'm making a game in Powerpoint. It's a complex game, where you get to move around through mazes and seas. You therefore need to be able to move to every single "square" or grid location not taken up by a "rock", aka wall. In some parts of the game, you need to go around collecting things, and once you have, I would like it so that the image of the thing that you pick up turns invisible for all slides in a set duration of slides, or a map. I was wondering if this is possible, and if so, how?