For Aslan, that one week was spent hiding from Lucius while trying to complete his final masterpiece as quickly as possible. Because Lucius kept pestering him, and because he didn't want the Roman Emperor to guess that he was Estée Lauder, Melusine even had to maintain her dragon form for the entire week.
For the departing steppe warriors, that one week was for returning to their own territory to resupply, awaiting the next round of invasion and plunder.
Likewise, one week was already enough time for the departed King Arthur to land on the continent and charge inland. As mentioned before, because wars frequently occurred in the east, the eastern army was significantly stronger than the western one. Furthermore, with Emperor Lucius personally leading the troops to campaign in the east, the elite forces were naturally all transferred to the eastern front.
On top of that, the combat strength of the entire west had grown lax due to a life of luxury. The knights following King Arthur on her eastern expedition were her most loyal followers. Moreover, the sense of contrast brought about by the prosperity of Rome fueled the soldiers' motivation to fight even more. After all, this victory could very well bring change to their families!
Look at that fine wine, look at that food! The nobles here were so extravagant they even used fine wine for bathing?! What kind of feeling was it for some of the knights from Great Britain, upon finding the room with the strongest smell of wine and preparing to celebrate, only to discover that all the fine wine had been poured into a bathtub? Today, they couldn't even be sure if the wine had been bathed in. But by the same token, this also meant that these nobles had even more, better-quality wine.
Envy, jealousy, and a tiny bit of hatred, combined with a blitzkrieg-like approach, it didn't take long for the territory of the Governor of Gaul to be taken down directly. Looking at the Governor of Gaul's fat-headed, big-eared appearance, the expressions on the faces of the knights present weren't very good. The nobles of their Great Britain were not so massive in stature! Was this a noble? This was a pig!
The Governor of Gaul never imagined that the Isle of Britain, which they had abandoned, would possess such strength. What a joke! Wasn't he just the king of that western island? How could this be the result?! He couldn't understand, he couldn't understand it at all!! But what did it matter if he couldn't understand? His incomprehension wouldn't stop his head from being lopped off by the knights of Great Britain.
At the same time, the entire treasury of Gaul would be transported back to Great Britain, including the sword hanging at the Governor's waist—the treasured sword Clarent, which also represented the royal sword of rule over the region of Gaul. What the Round Table Knights didn't expect was that when this sword was sent back to Great Britain, it would be used directly by Mordred.
Lucius, on the eastern border, directly received a communication sent by the Senate using magical means. After hearing the full story, a powerful surge of magical energy erupted from his tent. Even Aslan, who was in his mountain cave, paused abruptly, nearly making a mistake with his hands. This sudden burst of magical energy almost made him think someone had just used a Noble Phantasm-level attack to bombard the mountain he was on.
Stopping his work, Aslan quickly ran to the mountaintop and looked in Lucius's direction. He saw the Roman Emperor, who had been in his tent, walk directly out of the camp, draw his demonic sword, and unleash a strike on an empty patch of ground. This area, which had originally been a plain, instantly gained a small canyon. It became a relic with cliffs on both sides and a sword scar in the middle. Fortunately, the attack wasn't aimed in the direction of his mountain; otherwise, with a sudden strike like that, he would have had to redirect the lava ley lines all over again.
"You good-for-nothing who only knows how to ruin things—!!"
Aslan's mouth fell slightly open as he watched through his binoculars. It was truly the first time he had seen Lucius this furious. This was different from his excitement in battle. But considering the chain reaction of events and the future fate of the Roman Empire, the emperor's rage was understandable. Putting himself in his shoes, if one of his own subordinates had done something so brainless, causing the rear to collapse before the original front line had even been stabilized, he would have to borrow a classic line from a certain general—"I'll brick you into a goddamn statue!"
Huff... huff...
Lucius probably also understood that this was not the time to vent his anger wantonly. Compared to venting his fury here, it was better to hurry back. Every second he returned earlier could save a second's worth of losses. He couldn't really let the knights from Great Britain attack his own capital.
"All troops, hear my command! Half will remain to consolidate the eastern defense line! The other half, follow me back to the western part of the empire to eliminate the invading enemy!"
Fortunately, Lucius held absolute authority throughout the army. Although the soldiers were a bit confused about what had happened and were also very curious as to why their emperor was so furious, they ultimately said nothing more. Following orders, they began to split into two groups. One group consolidated the defenses in the eastern region, while the other began a forced march back to the west.
Aslan stood on the mountaintop, watching the gradually departing troops, his feelings complicated for a moment. Before witnessing King Arthur's end, he would first have to witness the end of this Roman Emperor.
"Farewell, Sword Emperor Lucius. Although I've only interacted with you twice, you are truly a hero. I hope you will have no regrets about your heroic end."
The final masterpiece in Aslan's hands was not yet complete. Moreover, from the current look of things, Artoria's eastern expedition was no different from the original story's timeline. Therefore, the outcome of this expedition should not change. If, by some chance—of course, just a chance, the possibility of this happening was something that would only occur in a forgotten world line—Artoria were to fail, then what Aslan would have to do was kill this Roman Sword Emperor, return to Great Britain, and, disguised as Artoria, grab Mordred for a good scolding.
By the time his final masterpiece was complete and he was piloting it back to Great Britain, he should be able to see the final outcome of Artoria and this Roman Emperor's clash along the way.
After watching Lucius depart, Aslan returned to the mountain's interior and began the final assembly and testing.
Aslan did not notice that, at the same time he turned around, the space behind him seemed to distort slightly. It seemed some existence was watching Aslan's every move. Only after Aslan's figure had completely disappeared from the mountaintop did this unseen presence gradually vanish.