New Viceking

  • You can't. This is from ingame help page:

    No other player may take the place of the king or vice king, even if they decide to leave the game. If one of the partners leaves the game, the vice king slot will remain empty. A kingdom may only unite once. If both kings quit the game, the kingdom is dissolved. As such, kings that are looking to unite should consider this as a commitment to their group for the remainder of the game world, and only agree if they're certain that they can and want to lead this kingdom until the very end.