This is just plain idiotic. It's not your position to dictate who can or can not play this game. As far as I'm concerned, Blockland can be for anyone and everyone under every age group who has an affinity for lego or just wants to play it. This game isn't going to get an enforced age rating just because of the behaviour of the online community. If a minor really wants to go online and risk mental traumatization, and his parents aren't bothered about it, then he can so bloody well please himself. Otherwise, he can always play offline.
You know what Junior? Since you're twelve years old, I've decided that you're too immature and should not be playing this game. I'm here to say NO, anyone not of a mature age should never play Blockland. Hell, technically because you're not thirteen yet, you're still legally a child, and shouldn't even pass the terms of service upon registration to this forum. Now is that fair?