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public class Damage extends Actor
{
    int time = 0;
    
    /**
     * Act - do whatever the Damage wants to do. This method is called whenever
     * the 'Act' or 'Run' button gets pressed in the environment.
     */
    public void act() 
    {
        time--; 
       if(time == 0)
       {
           getWorld().removeObject(this);
        }
        
    }    
    
    public Damage()
    {

        getImage().setTransparency(80);
        time = time + 10;  
       
        }
    }

import greenfoot.*;  // (World, Actor, GreenfootImage, Greenfoot and MouseInfo)

/**
 * Write a description of class MyWorld here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */
public class MyWorld extends World
{
    //int turned = 0;
    Hands hands = new Hands();
    int difficulty = 1;
    /**
     * Constructor for objects of class MyWorld.
     * 
     */
    public MyWorld()
    {    
        // Create a new world with 600x400 cells with a cell size of 1x1 pixels.
        super(1000, 563, 1); 
        addObject(hands, 600, 563);
        addObject(new TestWall(), 386, 396);
        addObject(new TestWall1(), 469, 312);
        addObject(new TestWall2(), 491, 269);
        addObject(new TestWall3(), 442, 271);
        addObject(new TestWall4(), 840, 398);
        setPaintOrder(Duck.class);
        setPaintOrder(TestWall.class);
        setPaintOrder(TestWall1.class);
        setPaintOrder(TestWall2.class);
        setPaintOrder(TestWall3.class);
        setPaintOrder(Hands.class);
        setPaintOrder(Damage.class);
        
    }
    
    
    
    public void act()
    {
        if(Greenfoot.getRandomNumber(300) < difficulty)
        {
            addObject(new Duck(), 370, 400);
            addObject(new TestWall(), 386, 396);
        }
        if(Greenfoot.getRandomNumber(300) < difficulty)
        {
            addObject(new Duck(), 473, 283);
            addObject(new TestWall1(), 469, 312);
            addObject(new TestWall2(), 491, 269);
            addObject(new TestWall3(), 442, 271);
        }
        if(Greenfoot.getRandomNumber(300) < difficulty)
        {
            addObject(new Duck(), 840, 380);
            addObject(new TestWall4(), 840, 398);
            
        }
        if(Greenfoot.getRandomNumber(30000) < 1)
        {
            difficulty++;
            
        }
    }
    
    
    
}