Legal Question in Legal Ethics in Georgia

Is this a legal question? The answer is, it depends.

First, we do not have any lawful games of the kind that you describe. It is not lawful to hunt and kill another man (leaving aside the questions about the dubious legality of the United State's alleged execution of Osama bin Laden). It is never lawful for anyone to hunt and kill another human being unless to protect oneself or another human being from deadly force/torture.

Deadly force is usually only justified by the need to protect oneself or others. Since the man "agreed" to play the game, one could argue that his agreement was voluntary and that his use of deadly force on the hunter was not justified by any exceptions, thus making him guilty of murder or manslaughter (a lesser degree of murder). However, one could also argue that he was protecting himself and, therefore, justified as he was threatened with (I would assume) lethal force if he did not act.

Whether such an argument would succeed or not depends on many more facts than you relate. For example, whoever gave the man that awful choice is essentially blackmailing the man. Why did he not go to the police? Could he have safely retreated from this awful deal rather than carry it out? I don't know.

Even if the facts don't rise to justification, it may be sufficient, depending on the man's beliefs and whether they were reasonable or not to reduce the degree of murder from murder in the first degree to a lesser count or voluntary manslaughter.