In his original world, Aegon's plan was undoubtedly to compete with banks for business, which was tantamount to going against the state machinery. A large charge of illegal fundraising would be brought against him, and he would be in deep trouble.
But in Westeros, where the economy and financial industries are almost blank slates, not to mention there are no relevant laws at all, even if there were, with Eddard Stark currently serving as Hand of the King, the Night's Watch would definitely be able to obtain the right to legally raise funds.
Aegon was not born studying economics; more accurately, he should have been completely ignorant of it. Fortunately, before crossing over, he often visited a forum called "Bihu". In that place where elites from all industries coexisted with story writers, and experts debated with habitual braggarts, he not only learned to quickly weave stories and be witty but also genuinely grasped some shallow inside information and obscure knowledge that ordinary people often wouldn't know – and these were now coming into use.
What he wanted to do was indeed robbing Peter to pay Paul, commonly known as a Ponzi scheme – at least until he found a way to make money. Tyrion quickly realized this, which is why he initially firmly refused to participate.
But at a critical moment, he had a flash of inspiration and, in a not very accurate or professional, but relatively easy-to-understand way, explained to Tyrion how a larger scheme worked. A fact that most people don't understand, wouldn't want to believe even if they did, whether they believe it or not is actually irrelevant, but is absolutely true: modern society indeed operates on this huge scheme that builds itself with "non-existent money." This great display of human imagination is far more important than any technology or new invention, and when everyone participates, it can no longer be called a scheme.
What Aegon did was use this super scheme, far more exaggerated than robbing Peter to pay Paul, to broaden Tyrion's horizons and increase his tolerance for the fundraising he was about to undertake, using a method of fighting fire with fire. He did not tell Tyrion about the potentially disastrous consequences of mishandling finance, nor was he sure whether his attempt to bring these concepts into this world was right, nor did he know if his plan would ultimately succeed... But he had to put on a confident appearance – if he himself looked doubtful and hesitant, how could he convince a feudal noble who was encountering this knowledge for the first time?
Having a Lannister join was not a necessary condition, but if Tyrion was willing to cooperate, everything that followed would be much smoother.
He still wanted to take off the black clothes and return to his original world. He couldn't and didn't want to spend every day just busy raising the ransom to exchange for his freedom. After much thought, "fundraising" was the only method he could currently think of to solve the funding problem once and for all.
***
Aegon was really busy.
First, he had to go see which two assistants the respectable Hand of the King Eddard Stark had arranged for him and where the office was located. Although both these matters could actually be solved with money, at the current stage before fundraising began, it was naturally best to save as much as possible.
Then, he had to arrange matters related to sending the first 'ransom' Tyrion paid him to The Wall.
Finally, he also had to prepare for a trip to Dragonstone to get the dragonglass mining work ready.
It didn't seem like much, but in this era, just traveling back and forth for anything took a lot of time. He had just gained his freedom and taken on a new post, so he was naturally cautious and didn't dare to be lazy at all.
He and Yoren rushed to the base of the Red Keep, found a place to have lunch, and then entered the Royal Castle again, arriving at the base of the Prime Minister's Tower. The King's Hand was far busier than the crosser; they didn't get to see Eddard Stark again. Yoren was taken directly to the dungeon, while Aegon also met the two Stark guards assigned to assist him, Oden and Davie.
The two Soldier from Winterfell inherently possessed the North's passive attribute of friendliness towards the Night's Watch. After the three of them got acquainted in a harmonious atmosphere, Aegon was led by them to the East Camp of the King's Landing City Watch.
Here, he met the current Captain of the King's Landing City Watch, Janos Slynt, a short, stocky man with a bald head, a double chin, and a lecherous face.
Aegon had no good feelings towards this man who was openly corrupt, sold offices and titles, and who betrayed Eddard Stark in the original story. The latter was clearly uninterested in a Night's Watch member from The Wall who seemed unable to bring him any benefits. Fortunately, this matter was ordered by the Hand of the King, so despite wearing a sour face, the Captain of the City Watch didn't dare to obstruct or cause trouble. After nodding as a greeting to Aegon, he casually assigned a Gold Cloak to take Aegon and the other two to see the house that was now to be the Night's Watch Office.
...
The house was located opposite the gate of the King's Landing City Watch's East Camp, not far from the noble district and the Red Keep. As it belonged to the City Watch and was located on a street with huge pedestrian traffic, even the money-grubbing Janos Slynt didn't dare to take it upon himself to rent it out for business. Thus, after being vacant for a while, it was conveniently taken by the Night's Watch who happened to seek out Eddard.
To be honest, Aegon was very satisfied with the result. A storefront like this, close to the street and adjacent to King's Landing's security forces, would likely cost more than all his gold and silver coins combined for a single month if he had to rent it himself. Seeking help from Eddard Stark was indeed the right move; this was definitely quite considerate towards the Night's Watch.
After seeing the house and getting the key, Aegon took the two guards from Winterfell back to the inn he was staying at to meet up with Tyrion. As the sun began to set, they left the Albatross Inn and headed to the port and merchant area of King's Landing along the Blackwater River to begin purchasing supplies.
Passing through Street of the Sisters, Mud Street, and Fisherman's Square all the way south, after exiting the River Gate, also known as the Mud Gate, they arrived at their destination.
...
The Mud Gate wasn't muddy at all. It got its name because people disembarking at the port here often had wet mud on their feet. When the traffic was heavy, it led to mud everywhere on the roads and squares, and after rain, the road conditions were as bad as walking into a swamp.
Three hundred years ago, this area was completely covered by forest, with only scattered fishermen settling on the north bank of the Blackwater River, whose waters were swift and plunged deep into the sea. Later, Aegon the Conqueror crossed the sea from Dragonstone, and his army landed here. Now, this has become the most prosperous area outside the walls of King's Landing.
Houses, pavilions, brick warehouses, wooden inns, and market stalls, taverns, cemeteries, and brothels, various buildings stood one after another, and the noise could be heard from afar; over a hundred docks lined the waterfront, and countless ships were moored in the harbor; deep-sea fishing boats and river ferries came and went endlessly, boatmen punted back and forth across Blackwater Bay, and merchant ships continuously unloaded goods from Braavos, Pentos, and Lys.
This is the largest port for external trade in Westeros. To provide space for the Fisherman's Square inside the city walls and the cargo distribution center outside the walls, the city walls and gates here are the weakest points in King's Landing, which also makes the nickname "Mud Gate" more fitting.
Tyrion knew almost every merchant with a name at the port, and with his Lannister family's "Little Imp" mind and reputation, basically no one dared to cheat him. Aegon was happy to take it easy on this matter, simply following along, watching the Dwarf skillfully negotiate all the transactions and arrangements for the ransom he had paid, at a cost slightly lower than expected: from confirming the price and delivery date to hiring ships to transport the supplies to Eastwatch-by-the-Sea, he didn't have to worry about anything. His freedom for at least the next three months was thus secured.
And the first task for the two Winterfell guards was to ensure that this batch of supplies arrived at Eastwatch-by-the-Sea on time, in good condition, and without any loss, to be delivered to the Night's Watch.
Night fell. Before dark, Aegon found a small merchant ship that was recently heading to Dragonstone. After paying a deposit of a few silver stags, the captain agreed to wait for him to board before departing the next day... Everything was settled, and the night was deep. Thus, Aegon's second day in King's Landing passed busily and productively.
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