In the meantime, Tarkin had began bombarding the northern hemisphere from the Sovereign. Raddus kept his Cruisers on hold for the time being, keeping the Imperial forces in the south at bay. Moff Tarkin claimed that he had built himself a fortress. In addition to those, Raddus took five Star Cruisers and a number of smaller vessels from the Mon Cala Mercantile Fleet and linked their shields together, making a large shield bubble that was impenetrable to the Imperial attackers. Raddus began using two primary tactics: the first was for the Mon Calamari and Quarren defenders to hole up in their under water cities and force the Imperial forces to fight them in the corridors the second was to scatter into the far reaches of the oceans, forcing the Imperial forces to split up, increasing their need to resupply. Lee-Char then sacrificed the surface of Mon Cala by having large creatures generate devastating waves, taking the Imperial forces away in the process. Once the surface cities were evacuated, Lee-Char sent Ackbar to defend the northern hemisphere and sent Raddus to defend the southern. A battle subsequently broke out in Dac City where Raddus stayed with Lee-Char and Ackbar, Lee-Char's Chief of Security, in the palace. Moff Tarkin responded to Telvar's assassination by sending his forces down to invade Mon Cala. Vader was confronted by Commander Gial Ackbar and Telvar's shuttle exploded as they discussed Vader's intentions on Mon Cala. Raddus discussed the possibility of Mon Cala seceding to Lee-Char but their conversation was cut short by Darth Vader as he and three Inquisitors arrived at Dac City. Influenced by a surviving Jedi, Lee-Char continued to defy Telvar's offers. Moff Wilhuff Tarkin parked the Sovereign above Mon Cala and sent ambassador Telvar to negotiate a trade deal with Lee-Char in Dac City. In 18 BBY, Raddus was for King Lee-Char's deteriorating negotiations between the newly-formed Galactic Empire and Mon Cala.

Raddus was present for the negotiations between King Lee-Char and ambassador Telvar. While his movements seem purely defensive, he undoubtedly has a counterattack in mind.' ―Wilhuff Tarkin to Bergon

Battle of scarif space