Both Viserys and Illyrio were brought back to Lorath where they were thrown in a jail. Illyrio was going to be publicly hanged for his crimes, while Viserys will get the blood eagle treatment.
The blood eagle treatment involved carving the victim's back open and cutting their ribs away from their spine, before the lungs were pulled out through the resulting wounds.
Viserys was in no way a threat to Maximus or his rule, but for his future plans he would be in the way, and he also was broken beyond repair as he constantly blamed Daenerys for their mother's death, and he was so power hungry on returning to claim his throne.
All Daenerys wants is to return home, she doesn't want the iron throne yet as she has no met Sir Jorah Mormont who slightly encouraged her to be queen instead of her brother.
Maximus had thought about indoctrinating Viserys making him completely loyal to Maximus so that he could see Robert's reaction to knowing that Maximus had a Targaryen serving under him, but he was not needed and plus why would he keep an abuser around his court even if he is completely loyal it would still remind Daenerys of what he used to do to her.
As for the matter with Illyrio, Maximus had changed his mind and would also give him the blood eagle treatment.
A Week later, in the courtyard of the Palace, Both Illyrio and Viserys were dragged to the courtyard and laid on their stomachs. Then a torturer approached and begin the blood eagle ritual.
Both Viserys and Illyrio were screaming, begging for their lives, as the torturer began carving their backs open and pulling their ribs away from their spine. Daenerys wasn't present for the ritual since she didn't want to see such a thing, but Maximus was present since of course he was the Emperor, and he had to see the punishment through to the end.
The rest of the ritual was followed by loud screaming as their ribs were being pulled away from their spine, and then their spine was pulled out.
All the Royal Guards present had to put up with what was happening and were glad that it wasn't them, since it looked extremely painful what was happening to them.
After the ritual, their remains were burned and throughout the Empire it was spread that both Illyrio Viserys were executed for treason and their crimes were posted as well.
Some of the former Magisters that were in the other cities of the Empire felt that the Emperor was cruel and not somebody to mess with. At first, the Magisters thought that since only their titles were taken away, they still held some power in the city.
But the governors of the cities were like brick walls and refused to listen to anything, they said, completely ignoring their request and ideas. They even tried bribing the Governors, but even that didn't work, so they decided to do things their own way, expecting the Emperor not to do anything to them since they thought that they were important as the former rulers of the city.
But this recent incident proved them wrong, since now they know that the Emperor don't care about them.
To Maximus, the Magisters were just normal people and no matter how much money they have or how much power they used to have now they are powerless old men with no political importance to him.
A couple of days after Viserys and Illyrio were killed, the news had already reached Westeros, and now it was revealed that there was still a Targaryen alive. To Robert, this was pleasant news since a Targaryen was killed, ending a claim to his Throne.
The news about Daenerys was hidden and Robert hadn't found out about her yet and was only told about Viserys.
The people of the Empire continued on with their daily lives after the death of Viserys and Illyrio. None of the common people were effected by this turn of events, since while Viserys and Illyrio lives ended, others moved on.
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In Slavers bay ever since the establishment of the empire slave trading has not been that profitable as the Empire fleet would attack any slave ships attempting to sell slaves in their waters and on land many slave caravans were attacked.
Still in Slavers Bay, slavery was still a thing as it has been around for so long that slaves don't know what to do if they are free.
The Slaves wouldn't know how to blend into society, as they would only have the experience of being a slave, which meaning being told what to do and forced to do things and beat if they didn't obey.
But in a few years or so all of that would end as the threat of the Empire was too overwhelming for the Slave trade and many already knew that it was only a matter of time before the Empire attacks Slavers Bay.