@Override
	public boolean isObstacle(Element e) {
		if (e == null)
			throw new IllegalArgumentException("The given arguments are invalid!");
		
		for (Element element : getGrid().getElementsOnPosition(getGrid().getElementPosition(destination)))
			if (!(element instanceof Teleporter) && (element instanceof Obstacle) && ((Obstacle)element).isObstacle(e))
				return true;
		
		return false;
	}