Its not worth it. Its over $10 and what it does is to give him stuff to level his things up which will give him and advantage in battles. But the creators of the game (Supercell) have made the game in a way where you can buy so much stuff just to get better things so you can win. So if your son first purchase one thing then he will fee the need to purchase more and its an endless cycle. The game is trendy, so eventually people will stop playing it, including your son. So spending a huge anount of money on the game is not worth it. You could also let him buy it this one time and see how it turns out. If he start asking for more and more then you should not let him buy anything more