The Boss Simulator

He played a simulator where the mission was to lead a faction, making it grow stronger and stronger until it reached the top.

On his first run, he became the head of a declining family in the Heian-kyo era. While he diligently farmed, did business, and earned money, he was suddenly attacked.

"System Notification: Your faction's defenses are inadequate. It has fallen to an attack by the King of Curses."

"System Notification: You have been killed by the King of Curses."

"Ending: Bad Ending: The Unknown Life of a Down-and-Out Family Head"

He was furious, but after looking over his family faction, he decided to endure the humiliation and inherit the next run. Reincarnating as the second-generation head of the same declining family, he resolved to see this scenario through.

The King of Curses had ravaged his former territory, and he was back to having nothing from the start. He endured it.

As he prepared to develop his family and hire people to hunt down the previous boss for revenge, he died again.

"System Notification: Your guards are inadequate. The Demon King attacked in the middle of the night, and your guards have been killed."

"System Notification: You have been killed by the Demon King."

"Ending: Bad Ending: The Frustrating Life of a Family Head Who Died Before His Time"

After dying again and again because he was so stubborn, he finally understood.

If he tried to develop his faction, he'd still die. If he wasn't strong enough, someone else would still steal the fruits of his labor.

Either find a powerful ally or become powerful himself.

...Or, if all else failed, maybe he could try clinging to a powerful ally?

Theme: Work hard and strive.