Hi I have a short game and I am still working on it. Harlock But I want to make it a scrolling world. I have tried multiple scrolling worlds found on this website but I can not get it to work. If someone could help me out with this I would be truly grateful. There is also one more error that keeps popping up. Whenever a actor move outside the screen I am getting this error : java.lang.IllegalStateException: Actor not in world. An attempt was made to use the actor's location while it is not in the world. Either it has not yet been inserted, or it has been removed. at greenfoot.Actor.failIfNotInWorld(Actor.java:681) at greenfoot.Actor.getOneObjectAtOffset(Actor.java:885) at Character.canSee(Character.java:28) at SandBal.removeBall(SandBal.java:33) at SandBal.act(SandBal.java:19) at greenfoot.core.Simulation.actActor(Simulation.java:583) at greenfoot.core.Simulation.runOneLoop(Simulation.java:541) at greenfoot.core.Simulation.runContent(Simulation.java:215) at greenfoot.core.Simulation.run(Simulation.java:205) I know what is causing it but I do not know how to fix it. If someone could help me with these 2 problems I would be very grateful. Thank you