Just checking is it against the rules for high level clan to declare war on a level 5 castle. They are going to attack him till he quits or leaves kingdom. (So they say) he said good luck with that.  Obviously not his main castle.  But still it seems a little ignorant. 

There's no rules against it but they won't benefit from hitting his city in resources but of course they can get kills. Why doesn't he simply use a shield if he doesn't have the gold then join a clan. Sounds a little weird to me that a clan would be that upset with a small account unless they know who it is. 

Lol, this biggie does not know what he has started. The level 5 named his castle to as close to other guys as the game will allow and now is looking for ways to iterate the the other guy. He has a level 5 and lots of gold and resources. He has exactly the amount of troops his hospital will hold and nothing to do but attack invaders to get experience for his hero and poke at this other castle. He does not think it is strange just fun. Played two other games he played in. You know the little kid poking his brother/sister this guy never grew out of that stage. He is now showing interest in the game. This guy will never get rid of him now and as he grows it Will only get worse.