Murdering their way into the palace > those who want to be the rulers have to kill all those that block their claim to the throne (which is in the palace ) >To kill/murder anyone who stands in his way to power Being murdered out of it > To be rejected or displaced from the throne by murder of those currently sitting on the throne > being murdered * out of his throne*

It would mean in order for them to have become the rulers of the palace they killed the previous rulers. However, once they gained power, they were in turn also killed in a rebellion. Their deaths made it possible for another to become the ruler. I hope that helps :)