Is there a way that i can make a ghost that cross a wall?
Not that I know of, but I don’t use many extensions. What I would try to do to mimic something like that is to have it so that when the player overlaps a tile (at location), in this case whatever one you are using for the wall, to just set the wall on at location so that the player can’t pass through. However, since these tiles do not have a wall to begin with, the ghost can move through them. One thing you will need to do to get this to work will be to have a forever loop that goes like this:
The blank tile represents whatever wall tile you are using. For the set wall off at 0,0 you will need to turn all walls back to off so that the ghost can pass through walls that you have tried to pass through.
I don’t know if there is an extension that would make this way easier, but this would be my best guess at making your ghost idea.
Go to the sprites tab > drag the “Set mySprite auto destroy on/off” and drag it in. As the variable set your character and change the “auto destroy” to “ghost trough walls”. Hope this helps.