public void tick(int y) {

		if ( y > 25000 ) {
		
		} else if ( y > 17000 ) {
		
			if ((y%100) == 0) {
				this.generateWing(y);
			}
			
			if ((y%1499) == 0) {
				this.generatePowerUp(y);
			}

		} else {
		
			if (this.bossBattle == false) {
			
				this.bossBattle = true;
				this.boss = this.enemyGenerator.makeBossEnemy(this.randomGenerator.nextInt(500)+100,y+50);
				this.hud.setBoss(this.boss);		
			}
		}

		if ((this.bossBattle == true) && (this.boss.isDead())) {							
				this.missionSuccess = true;	
		}
	}