Their first main goal is of the highest priority because the progenitor promised them a reward and because they want to infect and subdue the void universe for themselves.
Their second main goal is to subdue the corridor of worlds for themselves. Apart from their main goal are side goals that they intend to achieve along the way.
Their first side goal is to stop the god of power and take for themselves whatever it is that Beyonders have come to the void universe to take.
Their second side goal is to subdue more powerful entities and grow stronger. After all, only the most powerful beings should be able to make it to the core of the world.
The powerful entities they have their eyes on are the three consciousnesses that reward breaking laws, the overgod of the void universe, usurpers, the spiritual beyonder called the god of the soul, and finally the god of power.