Supposing I have a character or group of characters capable of assassination and subversion, or whatever else might be needed, what would they have to do? I suppose, the obvious is to kill the king, the queen, their sons and their daughters. The goal is to make it so there is no immediate successor to the throne, and the nobles aren't willing to concede it to any other. I suppose they might need to create some hostilities between the nobles that would be potential contenders to the throne. If that's the case, I would like some suggestions on what ways that could be achieved. What would press their buttons, and what buttons would those be? What other obstacles would have to be overcome?