God do so ... - Jehoram uses almost the very words of his wicked mother, when she sought the life of Elijah (marginal reference).
The head of Elisha - Beheading was not an ordinary Jewish punishment. The Law did not sanction it. But in Assyria, Babylonia, and generally through the East, it was the most conmon form of capital punishment. It is not quite clear why Elisha was to be punished. Perhaps Jehoram argued from his other miracles that he could give deliverance from the present peril, if he liked.