Prelude
See Battle of Hakata Bay.
Battle
Maxwell made a bold move immediately after gaining hundreds of thousands of reinforcements from around the planet: send the Ryuans through the Spirit World Portal and defeat the Tatians on their own turf. A few days later, the Ryuans had completely embarked and were following the Tatians through the Spirit World portal. Once they arrived, both sides set up camp, lined up their troops, and prepared for battle. The Tatians had their entire expeditionary force here, as well as ten thousand more Oni Demons. The Ryuans had their full army there, including crouching tiger cannons. The first move made was by Maxwell, who ordered the cannons to fire, killing over a third of the Oni Demons. While the cannons were being reloaded, the Tatians charged, with the Onis at the front of their lines. Keeping calm and level-headed after having prior experience repulsing Onis, the Ryuans intentionally made gaps in their lines that allowed the Onis to get through. They then started attacking them with naginata, either driving from the field or killing them all. By this time, the crouching tiger cannons were reloaded and were firing on the Tatians that were trying to charge them, sending them crashing back into their own lines. Taking advantage of this chaos, Maxwell sent all his cavalry to attack the front lines, disguised as monsters to keep the Tatian horses at bay. However, the Tatians held their ground and the Ryuans were repulsed. Unable to achieve the quick victory that they each wanted, both sides retired to their camps. The next morning, the Tatian front lines were greeted by another volley of cannonfire, as well as volleys of tanegashima shots. Since the Tatians no longer had any Onis to lose, Tate ordered a general attack on the Aureans when the cannons were reloading. Though slowed down by tanegashima fire, the Tatians got to the cannons fast enough to disable or destroy all of them. The Tatians then caught the Ryuans off-guard by sending in their cavalry, who the Ryuans thought they drove from the field the day before. Maxwell ordered his gunmen to redirect their fire from the Tatian infantry to the cavalry. While the cavalry were getting pounded by volley after volley of tanegashima fire, Tate's infantry was already halfway through the Ryuan right center when Maxwell had to personally intervene and lead a contingent of 50 men to attack from the rear and dislodge them. One of his friends and best generals, Delaney, was killed during this action. Once the Tatian cavalry was finally driven from the field (for good this time), the gunmen redirected their fire at the Tatian infantry, pushing them back to their own lines. The next morning, Tate brought the last 3 Oni Demons into battle. Maxwell, not wanting to kill his own family, ordered his army to harass the demons until they are unconscious, but not to kill them. However, those Oni Demons were only a distraction, as Tate tried to flank the Ryuans again with his infantry. In response, Maxwell sent his cavalry to dislodge them, which he succeeded in doing. As the sun was setting, both sides returned to their camps for the night. The next morning, Maxwell was sick of the stalemate and decided to try something new. He thinned out his lines, baiting the Tatians into a general attack. They fell for this, thinking they could break the Ryuans' thin lines. However, they bent rather than broke, surrounding them on all sides but the rear in a sort of bow. Seizing his chance, Maxwell ordered his cavalry to attack the Tatians' rear, trapping them and packing them so close together they could no longer use their weapons effectively. After an immense slaughter, the Jade Oni surrendered and Tate left the planet with his surviving troops.
Aftermath
After this long and arduous battle, the Tatians left the planet and the Oni Demons were evicted from the Spirit Realm, being forced to live out the rest of their eternal lives as ordinary citizens of Ryu 97. Emperor Aaron abolished the planet's strict class system and decided upon a policy of modernization and industrialization. Modern technologies were imported from the Ishgas and Aureans. The Samoorai/Ashigaru system was abolished and replaced with a conscript army and numerous other reforms were made.