That might seem like a strange question, because the entire game is about threatening and attacking.
But what if someone says in chat, "Don't attack me, or I'll suicide on you. I don't care if it costs me the game." -- Is it wrong (legally? morally?) to make the threat in the first place? And is it wrong to act on it? Could this fall under the rule against "throwing the game"?
What about variations. For instance, someone who declares in chat, "If you break my bonus next round, I'll break your bonus for three rounds minimum, no matter what it costs me."
And if you think either the stronger form of this threat, or any weaker variation, is unfair, would it warrant a negative feedback? Would it warrant any stronger action (from admin staff or whatever)?