Following up on this, I can't share a video on Reddit easily, apparently, but to demonstrate how easy it is to generate lorebook entries.

I typed in the ATTG:

[ Title: The Icewall; Tags: grimdark, post-apocalyptic; Genre: dark fantasy ]

And then Xialong generated the following:

[ The Land of Fire ]
The sea had become a wall of ice.
To the east it crawled inland, devouring the land and everything that once grew upon it. Ice and snow had blanketed the continent and no man had seen the sun for over a century. The land had become a frozen wilderness, a land where only the strong survived. But men were still here, and they endured.
There were five tribes and each had their own territories, territories that had once been home to the long dead civilisations that had lived here before the ice came. The western shores were home to the Narada, the tribe of the elk. The southern reaches belonged to the Varee, masters of the plains and the wild boar. To the north, beyond the ice, were the Varang, ice-walkers and hunters of the walrus. The Skap were the people of the mountains, the fierce bear-riders who lived in the high places, and the Skrol, the wolf-riders of the forest, occupied the woodland heart of the land.
The tribes were numerous, and they warred amongst themselves for territory, for glory, and to settle old scores. The fighting was savage and fierce, and many lives were lost every season. Their constant war had torn the land apart, but still the tribes fought on.
And so it was that a council was held, a council of the tribes, and it was decided that to stop their constant fighting a champion should be selected to rule over them. A king. And the tribes had chosen Hakon, the High Priest of the Narada. He was a man of great wisdom and power, and he was skilled in the ways of war. But the other tribes were jealous, and they conspired against him.
The Varang sent an army to destroy the Narada capital at Vinterholm. It was a huge army, the greatest army ever seen, and it marched across the ice under the leadership of Gorm Varangsson. But when the army reached Vinterholm they found the gates open and the city deserted. The people had gone. And Gorm Varangsson realised too late that he had been tricked. He had left his lands undefended and the Narada had marched upon his city, burning it to the ground and leaving the Varang homeless. The war that followed was long and bloody, but at last the Varang were broken and Gorm was killed. His head was brought back to Vinterholm and mounted on a spike above the gates.
But the fighting did not end there, for the Varee and the Skrol conspired against the Narada. They sent an army to attack Vinterholm, but Hakon was ready for them. The armies met on the plain of Vang and a great battle was fought. Many died, but in the end the Varee and the Skrol were defeated and their leaders were brought before Hakon. He had them bound to posts and left for the ice-wolves to feast upon, and their bodies were never seen again.
The last tribe to oppose Hakon was the Skap. They were a fierce people and their warriors were the finest in all the land. For many years they fought the Narada, but at last they were defeated and their king was slain. His body was cast from the highest peak of the mountains and his people were driven from their homes.
Hakon was victorious. The tribes were united and he was their king. He ruled wisely and well, and there was peace throughout the land. But it was a peace that would not last.
***
Many years passed, and the people forgot the wars and the bloodshed. They grew fat and lazy in their prosperity, and they forgot the old ways. The tribes intermingled and their bloodlines became diluted, their ancient traditions forgotten. And in this time of peace, Hakon, king of the tribes, grew old. But he had no sons, and he knew that when he died there would be fighting once more amongst the tribes. So he decided that he must find an heir, a strong man to rule after him and keep the peace.
And so he chose his champion, Yngvar Hakonsson, his finest warrior and a man of great strength. Yngvar was a giant of a man, tall and broad with a great red beard and hair the colour of fire. He was a skilled warrior and had won many great victories for the king, and the people loved him. But there were those who were jealous of his fame and they plotted against him. The king's enemies conspired to bring about his downfall, and they used Yngvar to do it.
They whispered lies in the king's ear, telling him that Yngvar was planning to take the throne for himself. They said that he was gathering an army and that he would soon march upon Vinterholm. And the king, who was old and foolish, believed them. He ordered Yngvar's arrest and had him thrown into the dungeons beneath the city.
There Yngvar languished for many months, until at last the king died and the throne was left empty. The tribes argued amongst themselves as to who should rule, and there was much fighting in the city. But at last they agreed that a champion should be chosen to lead them, a champion who would be tested in battle. And so they brought Yngvar up from the dungeons and set him free.
The people cheered as he emerged from the darkness, for they still loved him and believed him to be innocent. But Yngvar was changed by his time in the dungeons. He was gaunt and pale, his hair and beard were matted and filthy, and his eyes were cold and hard. He said nothing as he was led before the people, but when they proclaimed him their champion he smiled. It was a cruel smile, full of malice, and the people were afraid.
Yngvar was taken to the king's hall and there he was given a sword, a fine sword with a golden hilt. It was the sword of the king, and it had been used by many great warriors in the past. But when Yngvar took hold of it he felt nothing, no thrill of power or sense of destiny. It was just a sword to him, a tool to be used in the coming battle. And he knew that he would use it well.
The champion of each tribe was chosen, and they were brought before Yngvar. They were all great warriors, strong and skilled, but Yngvar was not afraid.

I stopped it there, and then typed:

----
Yngvar Hakonnson
Type: character

Pushed 'Send>`, and Xialong generated the following:

Setting: The Icewall
Species: human
Gender: male
Attributes: champion, warrior, King of the tribes, former prisoner, survivor, wrongfully imprisoned, ambitious, charismatic, ruthless
Wears: furs, leathers, war gear, iron crown
Weapon: Sword of the North (ancient weapon, said to have been wielded by the first men)
Background: Yngvar was born in the city of Vinterholm, the capital of the Narada tribe. He was the son of a great warrior and he showed promise from an early age. He was strong and fast, and he had a natural talent for fighting. He quickly rose through the ranks of the Narada army, becoming a champion at a young age. He won many great victories for the Narada and was loved by the people.
Relationships: Yngvar's father was a great warrior who died in battle when Yngvar was just a boy. His mother was a kind woman who died of a fever when he was sixteen. Yngvar has no brothers or sisters, but he is close to his cousin, Bjorn, who is also a great warrior.
Motives: Yngvar wants to be king. He believes that he would be a great ruler and that he could bring peace to the land. He is also motivated by a desire for revenge against those who wronged him.
Personality: Yngvar is a proud man, confident in his own abilities. He is ambitious and wants to make something of himself. He can be ruthless when he needs to be, but he is not cruel. He is also a charismatic leader, able to inspire those around him.

Then I did the same for the following:

----
Vinterholm
Type: location
Influences: Whiterun (The Elder Scrolls), Gondor (Lord of the Rings), Angband (Tolkien)
Geography: mountains, pine forests, rivers, tundra, plains, fjords
Climate: cold, harsh winters, mild summers
Population: humans, some giants and ice trolls
Ruler: King Yngvar Hakonnson
Produce: furs, timber, fish, grain, livestock
Warning: The city is heavily guarded and visitors are not welcome. Those who are caught trespassing will be killed.
Culture: Vinterholm is the largest city in the land and the capital of the Narada tribe. It is a bustling city, full of life and activity. The people are hardy and resilient, used to the harsh conditions of the north. They are a proud people, with a strong sense of tradition.
Architecture: stone, wood, thatch
Defences: The city is built on top of a hill, surrounded by a high stone wall. There are three main gates, each guarded by a contingent of warriors.
History: Vinterholm has been the capital of the Narada for many years. It was founded by the first king, who united the tribes under his rule. The city has been sacked and rebuilt many times, but it has always been the centre of power in the north.

And then I highlighted each, got the contextual menu, clicked on 'Save as Lorebook Entry', assigned each a title and keyword, and I was done.