Systems and methods are described herein for a hybrid liquid propellant rocket engine. In an embodiment, the engine includes a first pump powered by a first turbine, a second pump powered by a second turbine, and a gas generator. An output of the gas generator is connected to the first turbine and the second turbine. The engine further includes a third pump powered by a third turbine, a fourth pump powered by a fourth turbine, and a nozzle having an expander cycle in a wall and a combustion chamber. An output of the third pump is connected to the expander cycle and an output of the wall is connected to the third turbine and the fourth turbine. An output of the fourth pump, an output of the third turbine, and an output of the fourth turbine are connected to the combustion chamber.