The liege can also use a hook on the vassal to avoid tyranny. Obligations can be lowered at any time, but raising them will add +20 tyranny opinion unless the liege lowers the other obligation or provides the vassal a right. The feudal contract of each feudal vassal determines their obligations, which can only be changed one step at a time.
Each feudal vassal has a feudal contract, which can only be changed once per character and determines their obligations as well as whether they have special rights. They also have access to the Crown Authority law. Feudal governments can create new holdings and cadet branches.